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Steve Toy
02-02-2010, 19:09
Marco came round today with his tame sparky Matt to install a dedicated spur and consumer unit for my system (other sparkies tend to look at you as though you crawled from under a rock when you ask them to perform this particular task).

The main fuse was rather tarnished and underneath all the gunge after a bit of cleaning with Brasso it was revealed to be a 60 amp job that's probably been there since the house was built in 1971. A quick trip to HEP's Electrical Wholesale and we'd got the biggest fuse that would fit into the clips - an 80 amp Bussman. Marco and I then set about cleaning this fuse and its holder with Brasso and screenwash until they were shining like jewels.

A run of 10mm Twin and Earth was run from the mains inlet outside the back door to a board mounted on the wall just behind the system on which four unswitched MK sockets were connected to a Memera two-way Consumer Unit in a star-earth format using very short runs of 6mm T&E and 10mm earth cable.

Matt did a very tidy job that I'm confident will pass the WAF test when 'er outdoors gets home from work :eek:

The new spur arrangement is now in use and the effect it has had sonically is quite dramatic although it isn't quite finished yet. In a few days the boys will be back to bury the earth rods in the front garden in a star formation which should improve things further.

Before I describe the sonic effect in subjective terms and the anal retentive measurement freak objectivists' eyes begin to glaze over before going into scornful sneering sceptical mode, I shall give them a few measurements to consider:

Before the work was carried out

Impedance at the electricity meter: 3.5 ohms
Impedance at the switched MK sockets in use: 6 ohms

After

Impedance at the newly installed sockets: 2.3 ohms. :stalks:

Note this is lower than at the electricity meter before the install. The cause of this has to lie with the uprated main fuse and the cleaning of the contacts. Obviously such nerdery makes a difference - it can be measured! What gives me a considerable amount of saisfaction is knowing that the impedance on my hi-fi dedicated mains is lower than Marco's at 3 ohms. :ner:

...And,,,, the earth rods are yet to be fitted and this should lower the impedance some more. The installation is earthed of course, in the conventional manner for the time being.

As for the sound, we tried first of all connecting the system directly to the sockets on the board bypassing the Music Works Reflex block. The first thing I noticed was that the soundstage was bigger and deeper, Ray Lamontaigne's voice had much more presence and nuance but the effect was rather hi-fi and I wasn't engaged emotionally. The bass also had an irritating bloom and was a little one-noted.

So we put the Music Works Reflex back in and connected all the components to it. This was much better - more dynamic, better timing, more tuneful and the bass tightened up nicely. The theory says this should not make an improvement as the block is only going to raise the impedance, albeit only slightly. However, this is only part of the story.

Along with electrical properties we also have to consider the mechanical effects of microphony. The speakers kick out lots of noise into the room, this vibration is absorbed by the walls and then transmitted down the power leads back into the kit. The block effectively decouples the system from this vibration and with its laminated acrylic construction in a guitar shape, it is designed specifically to do just that. It is also star-earthed so we don't lose too much of the benefit of the new installation in terms of lowering impedance.

The net result is my system sounds cleaner, the noise floor is lowered significantly allowing it to reveal even more musical informaion. The headroom is also greater. Previously the sound would begin to harden with typical CDs at around the 11 o'clock position on the volume. We are now ok to wind the wick up to one o' clock before things begin to sound a bit on the harsh side. Sorry neighbours! :eyebrows:

The new mains installation:


http://img15.imageshack.us/img15/5011/newspur002.jpg (http://img15.imageshack.us/i/newspur002.jpg/)


Music Works Reflex Block plugged in:

http://img136.imageshack.us/img136/3816/newspur.jpg (http://img136.imageshack.us/i/newspur.jpg/)


The earth rods waiting to be buried in the garden:

http://img710.imageshack.us/img710/5772/newspur004.jpg (http://img710.imageshack.us/i/newspur004.jpg/)

CornishPasty
02-02-2010, 19:34
The service fuse isn't yours to change, it belongs to your electricity supplier and will peeps please stop refering to radial circuits as spurs. It's a dead giveaway that you're uneducated in electrical matters.

Please bear in mind when you sink those earth rods that they must be bonded to the main earth block situated near the cut out or in your CU. Failure to do this may result in a potential difference between two supposedly earthed parts which could prove fatal. It's a requirement of the regs and should be recorded on your installation certificate.

Kris
02-02-2010, 19:45
Very informative Steve, well done. As for the WAF factor, it's a FAIL I'm afraid as you didn't paint the wooden back board the same colour as the wall :(

One question if I may. Did you consider using 15amp round pin plugs and sockets? If not, why not?

As for changing the service fuse, and especially increasing the rating, yes, I was surprised to read that you did that . . .

Kris.

Dave Cawley
02-02-2010, 19:45
How did they measure the impedance?

Dave

CornishPasty
02-02-2010, 19:51
How did they measure impedance?

Dave


With an earth loop impedance tester I assume.

Kris
02-02-2010, 19:52
will peeps please stop refering to radial circuits as spurs.

A spur is a single cable extension from a ring circuit. A radial circuit is a single cable extension from the main CU. See, I'm learning! :)

Dave Cawley
02-02-2010, 19:54
OK, got it, for a moment I thought it was input to socket impedance. I'm struggling here though, if it is an earth loop impedance, what is the reference and how is it established?

Thanks

Dave

Steve Toy
02-02-2010, 20:02
The service fuse isn't yours to change, it belongs to your electricity supplier

I couldn't give a toss tbh. If it makes you feel better (:rolleyes:) I still have the old one to give back to them. :p

I'm sure they won't mind the fact that I've cleaned the contacts but I'm sure you'll be along to correct me there too.



and will peeps please stop refering to radial circuits as spurs. It's a dead giveaway that you're uneducated in electrical matters.


Did I ever say I was educated in electrical matters? Why do you think I got a qualified electrician to do the job?

Are you having difficulty in understanding precisely what I've had done? If not...


Please bear in mind when you sink those earth rods that they must be bonded to the main earth block situated near the cut out or in your CU. Failure to do this may result in a potential difference between two supposedly earthed parts which could prove fatal. It's a requirement of the regs and should be recorded on your installation certificate.

I'm sure the qualfied electrician is aware of this although he clearly won't know as much as you do.

Jonboy
02-02-2010, 20:04
Steve

Did you run the cable inside or outside of did i miss something, i have been considering running a new radial for my kit but the only way i can achieve this is by going around the outside of my house, i just can't bere the thought of having all the floors up again

I have to agere with Chris you should of painted the back board:ner:

Steve Toy
02-02-2010, 20:05
As for the WAF factor, it's a FAIL I'm afraid as you didn't paint the wooden back board the same colour as the wall :(



It is a fail. She absolutely bloody hates it. It's the consumer unit she mainly objects to.

Steve Toy
02-02-2010, 20:06
Jon, it's on the inside but the wiring is encased and it runs along the skirting boards.

CornishPasty
02-02-2010, 20:07
You clearly have a bad attitude Mr Toy.

Are your new sockets rcd protected?

Dave Hewitt
02-02-2010, 20:08
Steve.
As already pointed out by Cornish Pasty you cant go round changing mains fuses willy nilly,or installing earth rods ad hoc also what is you impedance test referenced to? and I'm not surprised that you now find things more HiFi instead of more real as before.I installed radials with 10mm cable and came to the same conclusion that you have ,the earth rods will probably make things more so.Its like bass from valves versus transistors one sounds like real instruments one sounds like hifi,no prizes for guessing which.
Dave.

Steve Toy
02-02-2010, 20:13
Mr Hewitt, You''ve only read part of the OP. Read the explanation of why it sounded more hi-fi and what the Music Works Reflex Block is for. Bear in mind that I've been using the block for a while and its use is my reference point.

Steve Toy
02-02-2010, 20:15
You clearly have a bad attitude Mr Toy.

Initially I wanted to delete your post but I decided to reply to it instead. The bad attitude began with your post, #2.

Dave Hewitt
02-02-2010, 20:20
Steve
Then why not wire the block into your consumer unit and do away with another set of sockets?
Dave.

Steve Toy
02-02-2010, 20:21
As already pointed out by Cornish Pasty you cant go round changing mains fuses willy nilly,or installing earth rods ad hoc


I just did - by a qualified electrician. What are you going to do about it? :ner:

The 80 amp fuse is also better from a safety POV.

It's my fucking house and none of your fucking business! :steam:

Steve Toy
02-02-2010, 20:25
Steve
Then why not wire the block into your consumer unit and do away with another set of sockets?
Dave.


I admit that three of the sockets are effectively redundant but the block needs to be portable.

Dave Hewitt
02-02-2010, 20:27
Steve
Dont get upset,but drop your insurance co aline tomorrow and see what they think,also you cant remove seals on fuses cause they are not yours ,and how is abigger fuse safer?

DSJR
02-02-2010, 20:37
On a hopefully lighter note regarding regs, when we had our new central heating boiler installed, the electrics had to be modified and the electrician went ape regarding the necessity for an extra earth wire that had to be within a few feet of the gas meter. Since it wasn't easily possible to do this, he reluctantly agreed to leave things and the installation was downgraded to a "repair" or something similar as it wasn't a full installation.

In the shop I was at for 17 years, we had a fresh ring taken from the fuse-box (the electricians tightened all the wires in and out of the meter etc). There was a 30A supply to the dem room with a switch by the meter downstairs. The upstairs had a 15A ring via 16 double unswitched MK sockets and a second switch in the dem room for safety. Now the shop is fully B&O Solus all of this may well have been ripped out, but it worked well for us...

Steve Toy
02-02-2010, 20:39
If the installation meets the regs that's all they need to know. As for the fuse, it wasn't in a seal. The installation is too old.

The work was carried out by a qualified electrician. In any case, I couldn't give a toss about Nulab bureaucracy. Can anyone explain why it should be forbidden to change a fuse? If it were, I'm sure the electrical supplier would not have sold it to me. I think a couple of folks are getting a bit jobsworthy about all this. Can anyone point out a genuine safety issue here with changing an old tarnished fuse from 1971 for a shiny new one? The new fuse itself meets the regs and do you think the now long-gone electricity company from back then are going to get hot under the collar about me changing their fuse? If they are so bothered, I've kept it and they can have it back whenever they want it.

Jonboy
02-02-2010, 20:48
Without trying to upset you some more Steve the 60 amp main fuse was there for a reason as this is the rated fuse for the supplied incoming cable potentially you could make your incoming cables run a bit on the warm side, a mate of mine had a pair Krells in his system driving Apogee diva's, the 60 amp supply wasn't enough to run them so he had the road dug up by the elec board and had a new 100 amp supply cable run in, he had no further problems with the Krells running out off juice and the elec board were very happy with his new power consumption:lol:

I'm not being a jobs worth or whatever, i'm just going by what i know from electricans mates who have told me off for doing simular things like pulling the main fuse in the past.

Steve Toy
02-02-2010, 20:59
The electricity meter is due to be changed soon. If the guy who does it seems cool enough I'll ask him for his advice and for retrospective permission to change the fuse. If he spots without me mentioning it it I'll plead ignorance as I didn't do the work myself, it was done by a qualified sparky who works for a local authority.

I've kept the old fuse in any case.

Kris
02-02-2010, 21:18
The fact is that Steve, who is not a qualified Electrician, got a qualified Electrician to do the job, as he rightly should have done. If anyone has problems with the work that was done, it's not Steves fault, so don't have a go at him!

Getting back to it, Steve did you consider using 15amp round pin sockets and plugs?

Joe
02-02-2010, 21:18
Ooh, ta, that's just reminded me I need to send in a meter reading!

Mike
02-02-2010, 21:21
Steve did you consider using 15amp round pin sockets and plugs?

I could sell him four 15A plugs and sockets with gold plated contacts.

For a suitably outrageous sum, of course! :eyebrows:

The Vinyl Adventure
02-02-2010, 21:38
Glad your having fun steve! Don't kill your self though eh ;) :lol:

Joe
02-02-2010, 21:40
It is a fail. She absolutely bloody hates it. It's the consumer unit she mainly objects to.

Put your foot down. Tell her to knit a cover for the CU if she objects to its appearance.

Steve Toy
02-02-2010, 21:56
Joe, she's not happy with it but we've not fallen out over it.

Mike
02-02-2010, 21:58
OK, got it, for a moment I thought it was input to socket impedance. I'm struggling here though, if it is an earth loop impedance, what is the reference and how is it established?

Thanks

Dave

In simple terms, the impedance of the phase-to-earth loop is measured by connecting a resistor (typically 10 Ohms) from the phase to the protective conductor. A fault current, usually something over 20 A, circulates in the fault loop, and the impedance of the loop is calculated within the instrument by dividing supply voltage by the value of this current. The resistance of the added resistor must be subtracted from this calculated value before the result is displayed. An alternative method is to measure the supply voltage both before and whilst the loop current is flowing. The difference is the volt drop in the loop due to the current, and loop impedance is calculated from voltage difference divided by current.

Steve Toy
02-02-2010, 22:06
Glad your having fun steve! Don't kill your self though eh


It meets all the regs and was installed by a qualified sparky. The RCBOs in the CU make it safe and all the plugs are fused.

Hamish, it's your next move....

Joe
02-02-2010, 22:09
Joe, she's not happy with it but we've not fallen out over it.

Glad to hear it!

I've just read our electricty meter, and somewhat alarmingly, it was 66666!

Dave Cawley
02-02-2010, 22:55
In simple terms, the impedance of the phase-to-earth loop is measured by connecting a resistor (typically 10 Ohms) from the phase to the protective conductor. A fault current, usually something over 20 A, circulates in the fault loop, and the impedance of the loop is calculated within the instrument by dividing supply voltage by the value of this current. The resistance of the added resistor must be subtracted from this calculated value before the result is displayed. An alternative method is to measure the supply voltage both before and whilst the loop current is flowing. The difference is the volt drop in the loop due to the current, and loop impedance is calculated from voltage difference divided by current.

I'm still not getting it, but I really am in new territory here. Which is "the phase" and what is the "protective conductor" ?

And as a separate matter, how would this earth impedance drop give " soundstage was bigger and deeper " What mechanism would account for this?

Thanks

Dave

The Vinyl Adventure
02-02-2010, 23:01
It meets all the regs and was installed by a qualified sparky. The RCBOs in the CU make it safe and all the plugs are fused.

Hamish, it's your next move....

Yeah, il get there pretty soonish I recon gonna leave it a couple of months I think... The hifi has been doing an aweful lot of improving o it's own accord the last week and a bit now!

Steve Toy
02-02-2010, 23:04
And as a separate matter, how would this earth impedance drop give " soundstage was bigger and deeper " What mechanism would account for this?



Dave, it just does, ok?

Improvements to power supply often have this effect to my ears. I'll leave it to you the expert to explain to me how this happens.

Ali Tait
02-02-2010, 23:23
Dave,the phase is the live,and the protective conductor is the earth.

Ian Walker
02-02-2010, 23:31
Christ lads i dread to think what mood marco's gona be in when he reads this lot......after being deafened t daftness listening to RRRamstein all night:lol:


I'm off............................................

Joe
02-02-2010, 23:32
I snuck the Pope thread in whilst he was distracted.

Steve Toy
02-02-2010, 23:32
Ian, did you get the picture message?

Marco
03-02-2010, 01:13
Lol - just in from the Rammstein concert, and yes it was bloody painfully loud!! Amazing spectacle, though, and an absolute riot... :eek:

Anyway, guys, I don't have time just now to dwell on this, as I'm about to hit the sack, however just to correct this:


Before the work was carried out

Impedance at the electricity meter: 3.5 ohms
Impedance at the switched MK sockets in use: 6 ohms

After

Impedance at the newly installed sockets: 2.3 ohms.

Note this is lower than at the electricity meter before the install. The cause of this has to lie with the uprated main fuse and the cleaning of the contacts. Obviously such nerdery makes a difference - it can be measured! What gives me a considerable amount of saisfaction is knowing that the impedance on my hi-fi dedicated mains is lower than Marco's at 3 ohms.


Dafty boy, you've got the measurements wrong with the decimal point in the wrong place! :doh:

The impedance was .35 Ohms at your meter and .6 Ohms at the sockets of your existing house ring main (where your system was plugged into before).

After the work we carried out, it was .23 Ohms at your newly installed sockets (where your system is connected to now).... Therefore, in effect, the impedance on the mains supplying your hi-fi system has been reduced from .6 Ohms to .23 Ohms, which is less than half the value it was before!! This could only have a significant positive effect on the audio performance of your system - and indeed did!

The noise floor of the system, as a result, was audibly massively reduced when comparing the 'before and after' effects, soncially, resulting in much greater detail retrieval, increased soundstage width and depth, less perceived distortion, and improved musicality on every level, with the test Ray Lamontagne album. In short, the sonic improvements were a total no-brainer.

The impedance reading on my dedicated mains supply for the system (the last time it was measured some years ago) was .32 Ohms at the dedicated CU.

As for Steve's new wall sockets, yes they are RCD protected. And as for up-rating the main house fuse from 60A to 80A, there was no 'broken seal', as the existing fuse was housed inside an old bakelite holder, held together with a couple of screws.

Steve has got a heavy-duty electric shower fitted in his bathroom, powered by 10mm twin & earth cable from the incoming mains, so the electrician considered that the main house fuse would be better up-rated to 80A, taking into account the rating of the existing house wiring, so this was duly done, with benefit also being obtained in terms of his hi-fi system from further lowering of the impedance at the 'head' of the incoming mains supply due to a higher amperage main fuse being fitted :)

Ok, I'll post my thoughts tomorrow on the very significant improvements we heard, sonically, with his system after the new mains installation, but right now it's time for beddy-byes! :goodnight:

Marco.

twelvebears
03-02-2010, 06:07
Initially I wanted to delete your post but I decided to reply to it instead. The bad attitude began with your post, #2.

Ralph. I fairness, I would have to agree with Steve. The tone of the first line of your post came across like you were the Electric Police.

Also, regardless for Steve's personal electrical knowledge, I'm sure Marco's associate in this was a professional.

twelvebears
03-02-2010, 06:12
Joe, she's not happy with it but we've not fallen out over it.

Mmmm.... It's this particular conversation that I've got to have soon with Susy.....

I'm sure it'll be fine. :rolleyes:

Ian Walker
03-02-2010, 07:38
Lol - just in from the Rammstein concert, and yes it was bloody painfully loud!! Amazing spectacle, though, and an absolute riot... :eek:

Anyway, guys, I don't have time just now to dwell on this, as I'm about to hit the sack, however just to correct this:



Dafty boy, you've got the measurements wrong with the decimal point in the wrong place! :doh:

The impedance was .35 Ohms at your meter and .6 Ohms at the sockets of your existing house ring main (where your system was plugged into before).

After the work we carried out, it was .23 Ohms at your newly installed sockets (where your system is connected to now).... Therefore, in effect, the impedance on the mains supplying your hi-fi system has been reduced from .6 Ohms to .23 Ohms, which is less than half the value it was before!! This could only have a significant positive effect on the audio performance of your system - and indeed did!

The noise floor of the system, as a result, was audibly massively reduced when comparing the 'before and after' effects, soncially, resulting in much greater detail retrieval, increased soundstage width and depth, less perceived distortion, and improved musicality on every level, with the test Ray Lamontagne album. In short, the sonic improvements were a total no-brainer.

The impedance reading on my dedicated mains supply for the system (the last time it was measured some years ago) was .32 Ohms at the dedicated CU.

As for Steve's new wall sockets, yes they are RCD protected. And as for up-rating the main house fuse from 60A to 80A, there was no 'broken seal', as the existing fuse was housed inside an old bakelite holder, held together with a couple of screws.

Steve has got a heavy-duty electric shower fitted in his bathroom, powered by 10mm twin & earth cable from the incoming mains, so the electrician considered that the main house fuse would be better up-rated to 80A, taking into account the rating of the existing house wiring, so this was duly done, with benefit also being obtained in terms of his hi-fi system from further lowering of the impedance at the 'head' of the incoming mains supply due to a higher amperage main fuse being fitted :)

Ok, I'll post my thoughts tomorrow on the very significant improvements we heard, sonically, with his system after the new mains installation, but right now it's time for beddy-byes! :goodnight:

Marco.
Blimey it must have taken you half the night to type that lot out:lol:

Rare Bird
03-02-2010, 09:06
I really feel sad for people pissing about with mains before the wall outlet :lol:

Dave Cawley
03-02-2010, 09:23
I'm even more confused now! I thought we were talking about earth impedances? It now seems it is supply impedances? Which is it, and what are the correct figures? My 1937 house could usefully benefit?

Do you have a PME system, and if so how do earthing rods work with this, surely this would set up additional earth currents? Or will the earth on that spur be only through the earth rods and not part of the PME system?

Lastly, is there a definitive site where this is all explained so that we can learn properly? I have just had a look and am more confused than ever............

Thanks

Dave

Themis
03-02-2010, 09:38
I'm like Dave, I would like to understand better. ;)

The Grand Wazoo
03-02-2010, 09:45
I'm like Dave, I would like to understand better. ;)

I'm with those two.
There's also a rather vulgar question I'd like to ask about the cost!

twelvebears
03-02-2010, 11:48
I'm with those two.
There's also a rather vulgar question I'd like to ask about the cost!

Me too. Have been considering this myself but would like to get an idea, and the work Steve had done would probably be similar to what I would be after.

John
03-02-2010, 12:14
I have a similar electrical set up to Steve and cost me about £500 a few years back Might of been £400 sorry memory bad

Marco
03-02-2010, 13:01
I'm even more confused now! I thought we were talking about earth impedances? It now seems it is supply impedances? Which is it, and what are the correct figures? My 1937 house could usefully benefit?


Hi Dave,

We're talking about supply impedances, mate. Steve's effectively less than halved the mains supply impedance for his system by carrying out the work he's had done, which as an engineer I'm sure you can appreciate the likely benefits. Going from .6 Ohms at the socket to .23 Ohms, isn't a subtle difference - it's a bloody fundamental one! :)

You will unquestionably always improve the sound quality of a system by lowering the supply impedance - this is an undisputable fact. Indeed, improving any part of the power supply chain in a system is always a no-brainer, as power supplies are at the heart of everything.

Looking at the measurements from Steve's set up, one can easily see how more cable and mechanical interfaces raises the impedance accordingly, as simply observing the difference in the impedance reading at Steve's meter (.35 Ohms) to the sockets in his house ring main (.6 Ohms) shows.

What's particularly interesting though, is that after the work has been carried out, Steve's achieved a lower impedance rating at his new dedicated sockets (.23 Ohms) than he initially had at his meter (.35 Ohms - taken when the old 60A fuse was in place)!! And that's simply because of fitting a higher rated main fuse (going from 60 to 80A) at the 'head' of the supply.

It's really very enlightening stuff this when you do it, and for a subjectivist, an absolute joy for once to obtain measureable evidence to confirm one's subjective sonic analysis.... :eyebrows:

And yes, I'm 99.99999% certain that your 1937 house would benefit. My 1897 one most definitely did!! ;)

Marco.

Rare Bird
03-02-2010, 13:01
You wont learn about this type of thing because in all fairness your not qualified electricians (you know those people who pay lots of money to go on training to do such to learn to be qualified)..If you don't know about all this don't let it worry you, just get a QUALIFIED electrician to do the wiring, if you ask him to do something that doesnt follow regulations he shouldnt be doing it..Honestly guys youlike to ignore someone stating that you need to loose as many contacts as you can in your amplifier power supply but your willing to fart about with something taboo to technically do the same thing as loosing the contacts does!

Steve Toy
03-02-2010, 13:17
I got a qualified electrician to do the whole job. Materials cost £170 + a day's labour.

Marco
03-02-2010, 13:29
You wont learn about this type of thing because in all fairness your not qualified electricians (you know those people who pay lots of money to go on training to do such to learn to be qualified)..If you don't know about all this don't let it worry you, just get a QUALIFIED electrician to do the wiring, if you ask him to do something that doesnt follow regulations he shouldnt be doing it..Honestly guys youlike to ignore someone stating that you need to loose as many contacts as you can in your amplifier power supply but your willing to fart about with something taboo to technically do the same thing as loosing the contacts does!

Sorry, Andre, I'm not sure what you're trying to say... :scratch:

Read my last post (#50) and explain what's not clear and/or what we (apparently) haven't learned.

It's all fully explained in there: subjective analysis backed up with objective measurable evidence, and all work carried out by an experienced qualified electrician, therefore I'm not sure what the point you're trying to make is?

Besides, your pal Russ Andrews championed all this stuff years ago. My 'obsession' with the mains started the day I read his 'The Power and the Glory' booklet about upgrading the mains supply! Most of this stuff Steve has done (as have I) is based on his (IMO correct) principles ;)

Marco.

Rare Bird
03-02-2010, 14:30
As for Steve's new wall sockets, yes they are RCD protected. And as for up-rating the main house fuse from 60A to 80A, there was no 'broken seal', as the existing fuse was housed inside an old bakelite holder, held together with a couple of screws.


Can i just point out that That large fuse should be in a sealed container, with a lead seal, if there isnt one it has been removed by someone. We have just had a new 100A box & fuse fitted by electric board, there a lead seal fitted on the new one aswell..I sugest you get the box resealed.

Another thang people who think it's smart to have hi-fi mains cables directly wired into a wall box is not smart, the fuse in each leads mains plug is there to protect the mains lead you shouldnt rely on your consumer unit tripping the lead fault..

Please don't use the term ''It's my house so fuck you'' maybe your house but regs are regs,saftey proceedures are saftey proceedures your insurance company will tell you to ''go fuck'' too.

Marco
03-02-2010, 14:45
Hi Andre,


Can i just point out that That large fuse should be in a sealed container, with a lead seal, if there isnt one it has been removed by someone.


Steve's must have been removed by someone else beforehand then, as there was no lead seal in evidence when the fuse was changed. I can assure you of that.


We have just had a new 100A box & fuse fitted by electric board, there a lead seal fitted on the new one aswell..

Maybe that's because it was new? Remember that Steve's house was built in the early 70s - indeed, as I pointed out earlier, the fuse holder was made from bakelite! ;)

I think the difference here is in the respective ages of the two boxes. Steve also can't be held responsible for someone else breaking the seal goodness knows how long ago!


Another thang people who think it's smart to have hi-fi mains cables directly wired into a wall box is not smart, the fuse in each leads mains plug is there to protect the mains lead you shouldnt rely on your consumer unit tripping the lead fault..


Maybe you've read it wrongly, Andre, but Steve's using fused plugs (and RCD-protected sockets) - his cables are not directly wired into a wall box, and thus his current installation meets the necessary regulations.

It's important we get the facts right here :)

Marco.

P.S Did you notice an improvement in the sound of your system when the new 100A box was fitted - what rating was it before, the same or lower?

Dave Hewitt
03-02-2010, 15:09
Hi
Can I ask how you measure supply impedance? because like Mr Cawley I am confused, you seem to be talking earth loop impedance at first but now its supply impedance.Are you just measuring the resistance if you like from begining to end of your new radial outlet?I'm genuinly interested in this and am not trying to take the piss.
Regards Dave.

Marco
03-02-2010, 15:18
Hi Dave,


Are you just measuring the resistance if you like from begining to end of your new radial outlet?


Yes, I believe that's the case, although I'm not certain. I'm unsure as to exactly what type of device the sparky used (but I will confirm when I see him next).

However, he simply plugged it into whichever sockets it were being tested, waited for it to read the information, and it came up with a value as a digital readout.

I'll ask him more about this method of testing when I see him next on Saturday... The bottom line is that the resultant sonic improvement was (massive) night and day - it was the sort of improvement normally gained by installing a much bigger, more capable, power amplifier :)

Marco.

Rare Bird
03-02-2010, 15:53
Hi Andre,



Steve's must have been removed by someone else beforehand then, as there was no lead seal in evidence when the fuse was changed. I can assure you of that.



Maybe that's because it was new? Remember that Steve's house was built in the early 70s - indeed, as I pointed out earlier, the fuse holder was made from bakelite! ;)



Our place was built before the 70's had also a backalite box, that also had a lead seal.I'm not saying steve removed it but someone did, it's best getting one back on, anything happens the inspectors will see it point finger.



Maybe you've read it wrongly, Andre, but Steve's using fused plugs (and RCD-protected sockets) - his cables are not directly wired into a wall box, and thus his current installation meets the necessary regulations.

It's important we get the facts right here :)



I know his leads are not wired but i've seen a lot who have..

As for RCD.. are unessisary on that Hi-FI dedicated supply, even so electricians will still say they are to be fitted, other socketry yes.

Improvement! :lol: been there done it.. Na all the cabling before the fused unit & the fuse were replaced for household high current items..

Marco
03-02-2010, 15:58
Cool :)


Improvement! been there done it.. Na all the cabling before the fused unit & the fuse were replaced for household high current items..


Do you already have a dedicated supply then for your hi-fi?

I didn't think you did - and if your system was plugged into the same supply being powered from the new 100A box, you should've have heard an improvement, unless your old one was also rated at 100A! ;)

Incidentally, so that we're clear, the improvement comes about from uprating the main fuse and wiring, not anything else.

What was the rating of your old box (and fuse) before the new installation?

Marco.

Rare Bird
03-02-2010, 16:10
I had a dedicated hi-fi power circuit in the last house i lived. the system cost a fortune & was completely wired with kimber kable.I'm not in that house now as i got divorced.I've explained the new 100A was fitted by the electric board in no connection to hifi but to point out both the new & old had lead seals.I DO NOT waste money anymore

Marco
03-02-2010, 16:22
You're not answering the point I raised in the second paragraph of my last post, though, Andre. If you don't want to answer it (for whatever reason) that's fine :)

Marco.

Rare Bird
03-02-2010, 16:25
Havent the faintest idea what the old rating was does'nt say on old bakerlite boxes & as they are sealed how can i! besides there's no dedicated hifi circuit in this house & never will be..

Marco
03-02-2010, 16:32
Lol, well that's one question answered at least! ;)

What I'm getting at mate (at the risk of repeating myself yet again) is that your old box was very probably rated at 60A, the same as Steve's because both your houses are from a similar era.....

*So*, as your hi-fi system is now being powered from the new higher-rated 100A box (along with every other electrical appliance in the house), it should (if your system has the necessary resolution to reveal the difference) sound better than when it was connected to the old, lower-rated, box - yes or no?

Am I getting though now, muchacho? Please say yes so that my sanity remains (reasonably) intact! :eyebrows:

Marco.

Mike
03-02-2010, 16:34
Hi
Can I ask how you measure supply impedance? because like Mr Cawley I am confused, you seem to be talking earth loop impedance at first but now its supply impedance.Are you just measuring the resistance if you like from begining to end of your new radial outlet?I'm genuinly interested in this and am not trying to take the piss.
Regards Dave.

I would bet good money (not too much though) that the device in question was an 'Earth Loop Impedance Tester'. I think a little bit of confusion is starting to creep in.

It's basic function is to give an indication of the safety of the installation, it does exactly what it says on the tin! ;)

The main idea (AFAIK) of a dedicated HiFi circuit (I would install a separate ring, personally) is to help keep noise that many household gizmo's feed back into the wiring away from your 'sensitive' HiFi gear. But the results can be variable and I reckon this 'impedance' thing is possibly not the holy grail. Can't do any harm though. :)

I've got one somewhere that I'll dig out and check my own wiring... my curiosity has been aroused.

Rare Bird
03-02-2010, 16:38
Lol, well that's one question answered at least! ;)

What I'm getting at mate (at the risk of repeating myself yet again) is that your old box was very probably rated at 60A, the same as Steve's because both your houses are from a similar era.....

*So*, as your hi-fi system is now being powered from the new higher-rated 100A box (along with every other electrical appliance in the house), it should (if your system has the necessary resolution to reveal the difference) sound better than when it was connected to the old, lower-rated, box - yes or no?

Am I getting though now, muchacho? Please say yes so that my sanity remains (reasonably) intact! :eyebrows:

Marco.

I listern to music not the mains supply mate don't give two fucks about all this shit no more :lolsign:

btw steve should have bought a good hifi CU ..Hager are the best..Seems to me half a jobs been done on a couple things, the internal wall wire for one.

http://www.hager.co.uk/service/downloads/general-catalogue/consumer_units/5616.htm

anthonyTD
03-02-2010, 16:42
Hi all,
I have read this thread with interest and would like to offer my opinion on the benefits of a low impedance power supply, and why its benefits are real in terms of gaining more info and insight from your system.

What I have written below is from a much earlier post I submitted after first joining AOS but is very relevant to this thread hence I thought I would resurrect it as I think it may help a few of you to understand the importance of low impedance power supplies, the thread relates mainly to amplifiers but if you understand where I am coming from you will realise why a low impedance mains supply is very beneficial for your audio replay system.

An audio amplifier as a whole can be described in its simplest form as a voltage modulator, and that’s where the problems start, because what you really want it to do in a perfect world is to only modulate forward of the power supply, for this to happen the power supply would have to have an ultra low impedance at all audio frequencies,[brick wall] in the real world this is far from the case in both valve/tube and solid state. This is mainly due to the way the power supply is designed, ie,using capacitor/resistor networks which not only have to supply the correct current/voltage needed for the complex audio modulations, but also it has to cope with the ripple current rejection needed for a smooth power transfer at all amplitudes of signal… Any Capacitor resistor network will only have relatively low impedances at certain frequencies; this is the main reason why all amplifiers have a particular sonic character, because to put it simple, they all have different impedance power supply characteristics. The reason you need ultra low impedance is to make sure that the analogue signal you are trying to reproduce cannot modulate the power supply, i.e., the lower you make the power supply impedance the less chance the signal has of modulating it!!! But this has to be a linear process, the power supply must have a low impedance at all possible audio frequencies!!! Capacitor resistor networks alone cannot possibly achieve this…
What happens when a power supply is able to modulate at certain analogue signals??? Simple, instead of the entire analogue signal being reproduced forward of the power supply, some of it will be lost through the power supply, and therefore won’t get any further down the chain. So, depending on where in the audio frequency range this critical low impedance occurs in the power supply of any amplifier, valve, or solid state, this will play a big part in the characteristics of the sound you get…
So, an ultra low impedance power supply at all audio frequencies is a must for a perfect transfer “forward” of all audio frequencies

regards,anthony,TD...

Marco
03-02-2010, 16:44
Hi Mikey,


I would bet good money (not too much though) that the device in question was an 'Earth Loop Impedance Tester'.


I'm 95% certain you're right. However, doesn't it also give a reasonable indication of the actual impedance of the supply?

There has to be some explainable correlation between a lower reading given by the 'Earth Loop Impedance Tester' (as was measured on Steve's supply), after he had the work carried out, and a (frankly massive) resultant improvement in the sound quality of his system...... :)

Your thoughts on the matter would be appreciated.

What the sparky told me is that the average reading at sockets on house ring mains is between .5 and .6 Ohms, depending on how many rooms a house has (and therefore how much cable and mechanical interfaces there are between the meter and the various wall sockets). Therefore Steve's reading at his dedicated sockets of .23 Ohms is massively lower than normal, and this appears to have a significant knock-on effect on how his system performs, sonically.

Perhaps try measuring the reading at the socket your hi-fi system is plugged into and let us know what it is?

Marco.

Marco
03-02-2010, 16:53
I listern to music not the mains supply mate don't give two fucks about all this shit no more :lolsign:


Mmmm... Best not go there, me thinks :eyebrows:


btw steve should have bought a good hifi CU ..Hager are the best..Seems to me half a jobs been done on a couple things, the internal wall wire for one.

http://www.hager.co.uk/service/downloads/general-catalogue/consumer_units/5616.htm


He's using a Memera one (recently taken over by another company, hence the different badge) and, IMO, these are every bit as good as Hager (I've had both). Hager were of course recommended by your 'guru' RA ;)

Marco.

Mike
03-02-2010, 17:04
doesn't it also give a reasonable indication of the actual impedance of the supply?

Not necessarily...

Mains Impedance is a measure of the total resistance to current flow in an electrical system. In practice, impedance consists of resistive and inductive elements. Mains impedance measurements are made by measuring the normal voltage (no load), then applying a fairly substantial load current. Impedance can be calculated as follows:


No Load Voltage - Load Voltage
------------------------------
Load Current


Since the impedance depends upon the ΔVoltage from no load to full load, it is important to use as large a load current as is practical for making impedance measurements.



This stuff is copy/pasted from notes I've got stashed on my PC. However, it all came from various t'internet sources that I can provide links for if anyone fancies boring themselves silly. :)

Marco
03-02-2010, 17:26
Excellent post, Anthony. That makes perfect sense even to a 'layman' like me! :)

Given what Mikey wrote about what is measured by 'Earth Loop Impedance Testers', which is what I think the sparky used in Steve's set-up, how does one accurately measure the actual impedance on the mains supply?

In effect, how would you replicate what Mike copied from his link below 'in the real world', as it were:


Mains Impedance is a measure of the total resistance to current flow in an electrical system. In practice, impedance consists of resistive and inductive elements. Mains impedance measurements are made by measuring the normal voltage (no load), then applying a fairly substantial load current.


Basically, how would I go about doing this and what 'kit' would I need to carry it out?

Marco.

P.S Mikey, I'll get to your earlier post in more detail in a minute after I've finished my dinner :cool:

Themis
03-02-2010, 17:26
Hi all,
I have read this thread with interest and would like to offer my opinion on the benefits of a low impedance power supply, and why its benefits are real in terms of gaining more info and insight from your system.

What I have written below is from a much earlier post I submitted after first joining AOS but is very relevant to this thread hence I thought I would resurrect it as I think it may help a few of you to understand the importance of low impedance power supplies, the thread relates mainly to amplifiers but if you understand where I am coming from you will realise why a low impedance mains supply is very beneficial for your audio replay system.

An audio amplifier as a whole can be described in its simplest form as a voltage modulator, and that’s where the problems start, because what you really want it to do in a perfect world is to only modulate forward of the power supply, for this to happen the power supply would have to have an ultra low impedance at all audio frequencies,[brick wall] in the real world this is far from the case in both valve/tube and solid state. This is mainly due to the way the power supply is designed, ie,using capacitor/resistor networks which not only have to supply the correct current/voltage needed for the complex audio modulations, but also it has to cope with the ripple current rejection needed for a smooth power transfer at all amplitudes of signal… Any Capacitor resistor network will only have relatively low impedances at certain frequencies; this is the main reason why all amplifiers have a particular sonic character, because to put it simple, they all have different impedance power supply characteristics. The reason you need ultra low impedance is to make sure that the analogue signal you are trying to reproduce cannot modulate the power supply, i.e., the lower you make the power supply impedance the less chance the signal has of modulating it!!! But this has to be a linear process, the power supply must have a low impedance at all possible audio frequencies!!! Capacitor resistor networks alone cannot possibly achieve this…
What happens when a power supply is able to modulate at certain analogue signals??? Simple, instead of the entire analogue signal being reproduced forward of the power supply, some of it will be lost through the power supply, and therefore won’t get any further down the chain. So, depending on where in the audio frequency range this critical low impedance occurs in the power supply of any amplifier, valve, or solid state, this will play a big part in the characteristics of the sound you get…
So, an ultra low impedance power supply at all audio frequencies is a must for a perfect transfer “forward” of all audio frequencies

regards,anthony,TD...
Thank you very much Anthony ! :)

Rare Bird
03-02-2010, 17:31
Wonder who will have the last word before the subject gets locked :lol:

Mike
03-02-2010, 17:36
Here's a bit of gumpf...

Earth loop impedance testing:- http://www.tlc-direct.co.uk/Book/8.6.2.htm

Mains impedance tester:- http://www.powerlines.com/zm100-a1.pdf (see 1.3)

Marco
03-02-2010, 17:51
I wonder if Dave C, as our resident measurements man, would be willing to acquire a mains impedance tester for us all to borrow (for a nominal fee ;)) to test our mains supplies with? :)

If it wasn't too expensive, I'd even be willing to chip in for half of its cost, as I'm genuinely interested in this stuff!

Or does anyone here already own such a device?

Mikey,

The above aside, this for me which I wrote earlier, is still the crux of the matter:


There has to be some explainable correlation between a lower reading given by the 'Earth Loop Impedance Tester' (as was measured on Steve's supply), after he had the work carried out, and a (frankly massive) resultant improvement in the sound quality of his system......


....and it's something I'd like to get to the bottom of. I've achieved the same result as Steve in my own system by doing a similar thing.

The fact is that even though 'Earth Loop Impedance Testers' don't 100% accurately measure mains supply impedance, whatever they do measure appears to be very relevant in terms of how a hi-fi system performs, sonically - so therefore something's going on........

Marco.

Steve Toy
03-02-2010, 18:00
I received this pm on the other side. I've had permission from the nice chap who sent it to post it here as long as he remains anonymous:



Cant be bothered argueing the toss with people who have clearly never heard well installed uprated mains, hence the private message.

The earth rod makes a difference but strictly speaking is against the electrical regulations if another type of earth is connected. The reason is that if you were relying on an earth rod alone, everything in your house would be protected by RCD's but if you have an earth from the supplier then everything may well not be covered by RCD's. This potentially means that in the event of a fault, and if the suppliers earth becomes disconnected, the earth rod can become live as the impedance would possibly not be low enough to allow disconnection of the MCB.

The upgrade to the main fuse can be confirmed with the supply company by your electrician. This comes under his assessmnent of maximum demand and diversity from the on site guide. I told my supplier that I was installing a 10Kw shower, and they upgraded the fuse. This made a big difference, as did polishing it.

Bear in mind with new uprated mains that it will take a good few weeks to burn in. One day it sounds great and the next it sounds off but in the end it comes right and sounds amazing. Best upgrade ive ever done. I used to sing its praises but got fed up with defending my position against the usual bunch of "know it all's".

Kind Regards

.....

Rare Bird
03-02-2010, 18:06
You sure you aint made that up ;)

Dave Hewitt
03-02-2010, 18:14
Hi all
Does this mean mains impedance has little effect as hifi sytems dont usually consume vast amounts of current and therefore littlevoltage drop is apparent if the quoted figure of .23 ohms is taken into account,or is this tosh.
regards Dave.

Marco
03-02-2010, 18:17
Haha - nice one, Steve! Or as Steve (twelvebears) affectionately referred to them earlier as the self-appointed 'electricity police' :wanker: :lol:

I almost dislike them as much as the self-appointed 'traffic police' I often encounter when out on the road!!

That chap should join AOS, as he has the right type of mentality.

I have no time whatsoever for idiots who insist on crapping all over other people's threads, where they're relating to others that they've discovered something which has genuinely improved the sonic performance of their system (and thus their enjoyment of music) for the sake of biased agendas, pointless pedantry, cynicism or plain old jealousy!

Thank goodness that on AOS we're sheltered from the blinkered bullshit of those tossers....

Bear in mind, however, that I'm not referring to people that have posted here who were simply genuinely concerned about the safety aspects of Steve's electrical supply installation (and mine). That's a different matter entirely :)

Marco.

Mike
03-02-2010, 18:21
There has to be some explainable correlation between a lower reading given by the 'Earth Loop Impedance Tester' (as was measured on Steve's supply), after he had the work carried out, and a (frankly massive) resultant improvement in the sound quality of his system...... :)

There may well be, but 'earth loop impedance' is NOT the same thing as 'mains impedance'.

I reckon much of the improvements could well have come from having nice fresh clean cable and connections, and separating (at least partially) the HiFi from the rest of the household crap floating around the ring main. :)

I've heard the 'higher rated' fuse trick mentioned many times though, so there's probably something to be said for it. Again, I'm sure nice clean contacts will at least be part of it.

Marco
03-02-2010, 18:28
Hi all
Does this mean mains impedance has little effect as hifi sytems dont usually consume vast amounts of current and therefore littlevoltage drop is apparent if the quoted figure of .23 ohms is taken into account,or is this tosh.


I don't know, mate. All I can tell you with absolute certainty is that the sonic effect (major improvement) achieved in Steve's system as a result of lowering the reading on the spark's 'Earth Loop Impedance Tester', through carrying out the work described, was very real and easily heard! It was the exact same in my system and also Ian's (although we have slightly different set-ups to Steve)

*That* is the bottom line and the only thing that really matters :)

Marco.

Marco
03-02-2010, 18:38
There may well be, but 'earth loop impedance' is NOT the same thing as 'mains impedance'.


I accept that, however lowering 'earth loop impedance' on the mains supply appears to have a significant effect on the sonic performance of a hi-fi system connected to it, regardless of how that is achieved, whether it is because of what you describe below:


I reckon much of the improvements could well have come from having nice fresh clean cable and connections, and separating (at least partially) the HiFi from the rest of the household crap floating around the ring main.

I've heard the 'higher rated' fuse trick mentioned many times though, so there's probably something to be said for it. Again, I'm sure nice clean contacts will at least be part of it.

...and/or the fitting of a dedicated ring or radial circuit.

What will be really interesting, though, is ascertaining the separate effect of installing the earth rods in Steve's set-up. I've been there and done that, so know roughly what to expect ;)

Marco.

P.S Do you own an 'Earth Loop Impedance Tester' or can you obtain one from work?

Dave Hewitt
03-02-2010, 18:47
Hi Marco,
Just done a little test with my amp mains lead,removed the fuse and fitted one of the copper blanks that we dont talk aboutand noticed adefinite difference to the sound,some would say better definitely a 'bigger' sound,so perhaps there is something in this.I dont know if the use of these blanks is legit or not.Will be trying further experiments soon.Hope this helps.
Regards Dave.

Dave Cawley
03-02-2010, 18:49
I'm not convinced that the measurement is the right one at all. But clearly the work done is good. I think the 'right measurement' would give the 'right conclusion'. You have to be careful with measurements, I know!

Clearly the work done was good and beneficial.

I'm still worried about earth rods and PME though.

Regards

Dave

Ali Tait
03-02-2010, 18:55
One thing strikes me-If the loop impedance tester is measuring the impedance at the socket,then at these low values,an iec lead plugged into the socket will raise that impedance,as it's another connector in the chain.It would be more accurate to measure the impedance at the iec where it plugs into the amp.
As I've said before,you need to be aware of the safety aspects of installing an earth spike.If there was a fault in the cable that supplies your street,it potentially means that the fault current could pass through your house into the earth spike.This can be in THOUSANDS OF AMPS! I've been to more than one funereal of a work collegue who had been killed by electricity.Most of you don't have the first idea of what you are dealing with.Nuff said.

swampy
03-02-2010, 19:00
[I]In simple terms, the impedance of the phase-to-earth loop is measured by connecting a resistor (typically 10 Ohms) from the phase to the protective conductor. A fault current, usually something over 20 A, circulates in the fault loop,

Thanks

Dave

ooooh, bet that resistor gets hot quickly. 240 / 10 = 24A, I^2 * R = P, P = Nearly 6000W (6KW)

I am with you on this. A bit beyond me on how they measure these things.

Marco
03-02-2010, 19:13
Hi Ali,


One thing strikes me-If the loop impedance tester is measuring the impedance at the socket,then at these low values,an iec lead plugged into the socket will raise that impedance,as it's another connector in the chain.It would be more accurate to measure the impedance at the iec where it plugs into the amp.
As I've said before,you need to be aware of the safety aspects of installing an earth spike.If there was a fault in the cable that supplies your street,it potentially means that the fault current could pass through your house into the earth spike.This can be in THOUSANDS OF AMPS! I've been to more than one funereal of a work collegue who had been killed by electricity.Most of you don't have the first idea of what you are dealing with.Nuff said.

That's definitely worthwhile pointing out. I think Steve will be having a chat with his electrician as to how best to ensure that the installation of earth rods is legal, and above all safe. He will then proceed (or not), as advised, with their installation :)

I would point out that earth rods for my hi-fi system have been installed in my garden since 2000, and were assured as being safe by a different (although equally qualified) electrician to the one Steve is using.

Marco.

Marco
03-02-2010, 19:17
Hi Marco,
Just done a little test with my amp mains lead,removed the fuse and fitted one of the copper blanks that we dont talk aboutand noticed adefinite difference to the sound,some would say better definitely a 'bigger' sound,so perhaps there is something in this.I dont know if the use of these blanks is legit or not.Will be trying further experiments soon.Hope this helps.
Regards Dave.

Hi Dave,

Yep, been there, done that one. Ian and I have concluded that although the sound is 'bigger', it wasn't to our ears better.

What Steve's done though with his mains supply is different, and of course he's using fused mains plugs with his equipment :)

Marco.

Marco
03-02-2010, 19:20
Hi Dave,


I'm not convinced that the measurement is the right one at all.


Neither am I. Fancy buying a proper mains impedance tester (as shown earlier by Mike) and doing the job correctly? :)


But clearly the work done is good.


Indeed - which is the main thing and all that really matters as far as Steve is concerned :cool:

Marco.

Barry
03-02-2010, 19:25
ooooh, bet that resistor gets hot quickly. 240 / 10 = 24A, I^2 * R = P, P = Nearly 6000W (6KW)

I am with you on this. A bit beyond me on how they measure these things.

That's why Earth Impedance Meters are so expensive. They are designed to measure the fault current and hence the impedance in only 40ms (2 cycles of the 50Hz mains), as RCBs are intended to take no longer than this to respond and operate.

I should also like to add my voice of caution to that of Ali Tait. Sloppy and ill-considered workmanship could have lethal consequences.

Regards

Marco
03-02-2010, 19:30
Hi Barry,


Sloppy and ill-considered workmanship could have lethal consequences.


I completely agree... Good job none of that has taken place in Steve's set-up so far, or will take place in future :)

Marco.

Mike
03-02-2010, 19:48
P.S Do you own an 'Earth Loop Impedance Tester' or can you obtain one from work?

I own one...

Dave Hewitt
03-02-2010, 19:49
Hi swampy
According to the manufacturer of these instruments its a pulsed supply for ashort period.
Dave.

Mike
03-02-2010, 19:53
One thing strikes me-If the loop impedance tester is measuring the impedance at the socket,then at these low values,an iec lead plugged into the socket will raise that impedance,as it's another connector in the chain.It would be more accurate to measure the impedance at the iec where it plugs into the amp.
As I've said before,you need to be aware of the safety aspects of installing an earth spike.If there was a fault in the cable that supplies your street,it potentially means that the fault current could pass through your house into the earth spike.This can be in THOUSANDS OF AMPS! I've been to more than one funereal of a work collegue who had been killed by electricity.Most of you don't have the first idea of what you are dealing with.Nuff said.

I can do that! :)

Mr. C
03-02-2010, 19:53
I suspect a few people are need of some serious therapy here :stalks:, consider yourselves as anally retentive as the Jaguar owners club. :steam:
A couple of points here, Steve used a qualified electrician who will have installed the upgrades safely and to the current regulations plus filled in the appropriate paperwork.
Regardless of the banality of how joe bloggs is trying to squeeze maximum froum brownie points on how to measure the earth impedance to the nth degree.
Sad factor 10 captain
Steve is just giving his insights as to how and why he wished this done..
Not everyone will go to this length, however it is a good read for this genuinely curious.
We install around 4-6 separate mains upgrades a month for hifi and non hifi clients, pretty sure non of them would be getting out the Preparation 'H' over this :lol:
Fitting of a seperate spur I feel is good upgrade at a modest outlay, providing you use a qualified sparky and explain to him exactly what you want and are trying to achieve.

Steve Toy
03-02-2010, 19:55
Why do you think I dragged a qualified electrician from the Northwest down here to do the job?

Ali Tait
03-02-2010, 19:57
I've no wish to start a thread war on this Marco,but I think this is worth pointing out from a safety point of view-The fact that you have had no problem up to now is neither here nor there.The fact is,you have no control over the cable that runs from your local substation and feeds your house and the properties around you.Granted,there may never be a problem,but if a fault did develop in this cable,under certain conditions you could see a huge fault current of thousands,even 10's of thousands of amps.The point I wish to stress is that this could happen at any time,and you have no control over this!

Just trying to keep people safe.

EDIT-note that I'm making this post in the context of fitting an earth spike in your garden.No reason the other stuff can't be done perfectly safely.

Marco
03-02-2010, 20:16
I own one...

Cool. Can you measure the reading at the socket your system is plugged into and let us know what it is, as well as what Ali suggested, so that we know what both readings are? I'm just curious :)

Marco.

Marco
03-02-2010, 20:20
Hi Ali,


I've no wish to start a thread war on this Marco,but I think this is worth pointing out from a safety point of view-The fact that you have had no problem up to now is neither here nor there.The fact is,you have no control over the cable that runs from your local substation and feeds your house and the properties around you.Granted,there may never be a problem,but if a fault did develop in this cable,under certain conditions you could see a huge fault current of thousands,even 10's of thousands of amps.The point I wish to stress is that this could happen at any time,and you have no control over this!

Just trying to keep people safe.

EDIT-note that I'm making this post in the context of fitting an earth spike in your garden.No reason the other stuff can't be done perfectly safely.

I don't have a problem with that (indeed I endorse your sentiments), so there's no need for any "thread war" :)

My point, however, wasn't that there hasn't been a problem (so far) in terms of safety with the installation of my earth rods, but rather that the electrician I used then advised me that it was safe, within the regs and legal - therefore if my earth rods set-up qualifies as such, there's no reason why Steve's can't too..... It's simply a matter of doing the job properly in the right way :cool:

Marco.

Marco
03-02-2010, 20:24
A voice of sanity writes:


I suspect a few people are need of some serious therapy here, consider yourselves as anally retentive as the Jaguar owners club.
A couple of points here, Steve used a qualified electrician who will have installed the upgrades safely and to the current regulations plus filled in the appropriate paperwork.
Regardless of the banality of how joe bloggs is trying to squeeze maximum froum brownie points on how to measure the earth impedance to the nth degree.
Sad factor 10 captain
Steve is just giving his insights as to how and why he wished this done..
Not everyone will go to this length, however it is a good read for this genuinely curious.
We install around 4-6 separate mains upgrades a month for hifi and non hifi clients, pretty sure non of them would be getting out the Preparation 'H' over this :lol:
Fitting of a seperate spur I feel is good upgrade at a modest outlay, providing you use a qualified sparky and explain to him exactly what you want and are trying to achieve.

:clap:

Marco.

Ali Tait
03-02-2010, 20:27
Ok,exactly how are the rods connected in your system Marco?

DSJR
03-02-2010, 20:34
Thank heavens we seem to have a good mains supply. I'm hearing more in my music than I've done in many a long year.......

Marco
03-02-2010, 20:37
Ok,exactly how are the rods connected in your system Marco?


Lol - I knew you'd ask me that! :lol:

The honest answer is, I don't really know as it happened 10 years ago! All I know is that there are five of them underneath the lawn somewhere, laid out in a 'star' formation, and that they're (in some way) connected to the dedicated CU for my system.

I'm happy though that the set-up is perfectly safe, as I was assured that it was at the time by my qualified electrician. However, I shall be listening intently to what Steve's electrician advises him in relation to the proposed installation of his own earth rods, and what is considered as safe and within the regs.

I will then use that information in future when recommending this type of set-up to others :)

Marco.

Dave Hewitt
03-02-2010, 20:52
Ali
Does it matter if the system is not pme and, how can anyone find this out.I have to confess that my system incorporates an earth rod adjacent to the consumer unit but if I am completely honest I think things sounded better before it was fitted.Will shortly be disconnecting same and having another listen.Will report back tomorrow.Before the radial circuits were fitted the system seemed to bounce along better if you see what Imean.In the past I have tried fitting bigger caps in power amp supplies and imo its not always worked its as if some sort of elasticity if you like has been removed and replaced by something keeping things under too much control and the life departed from the sound.Hope this makes sense to someone.Also Marco this bloody blouse you supplied is far too tight.
Regards Dave.

Marco
03-02-2010, 20:54
Also Marco this bloody blouse you supplied is far too tight.


:lol:

That's not a problem, sweety - we'll move up to the maternity range.

Marco.

Mike
03-02-2010, 20:57
Cool. Can you measure the reading at the socket your system is plugged into and let us know what it is, as well as what Ali suggested, so that we know what both readings are? I'm just curious :)

Marco.

I'll have to find it first...

Which means a trip into the cold, cold garage! :uhho:

Marco
03-02-2010, 20:59
............and possibly waking up that thing that 'lives' there :eek:

Marco.

Ali Tait
03-02-2010, 21:36
Dave,just interested in keeping peeps safe,though I may give this kind of thing a go myself.Maybe try a ring rather than radial and see if that makes a difference? I'll be interested in your findings with the earth rod.

swampy
03-02-2010, 21:56
Hi swampy
According to the manufacturer of these instruments its a pulsed supply for ashort period.
Dave.

oh, I thought it must be something clever.... Otherwise... Yes sir, this test instrument will measure your mains impedance but only once and it comes with a free fire extinguisher. :stalks:

Hope you have not put all those copper blanks everywhere !! :eek:

swampy
03-02-2010, 22:06
would it not be easier just to go down the mains re-gen route. Dusuun make one for a cheap price compared to PS audio offerings.

http://www.china-highend-hifi.com/prod01123412425.htm

Dave Hewitt
03-02-2010, 22:15
Swampy
You know it will be the wrong voltage from China.
Dave.

swampy
03-02-2010, 22:19
These things can adjust the voltage output and usually the frequency. Hence the led display and buttons I guess.

Just checked...

Scope of Input Voltage

AC 192 ~ 252 V

:p

Dave Hewitt
03-02-2010, 22:47
Swamp.
Nip round tomorrow am we'll have one knocked up before dinner,got this massive turntable supply.
Dave.

Marco
03-02-2010, 23:15
Nip round tomorrow am we'll have one knocked up before dinner,got this massive turntable supply.


Oooh, you stud... Is that the chat-up line you use on all the girls? :eyebrows:

I could dream up all sorts of twisted madness with that comment but we'll leave it there :lol:

Marco.

Joe
03-02-2010, 23:17
Swampy
You know it will be the wrong voltage from China.
Dave.

And the Customs will sting you for the import duty even if the leccy has 'gift' written all over it.

Marco
04-02-2010, 00:22
I wonder what would happen if people had them marked instead with: 'Warning - inside, inflatable Papal doll!'?

Marco.

Mike Reed
04-02-2010, 08:10
I wonder what would happen if people had them marked instead with: 'Warning - inside, inflatable Papal doll!'?

Marco.

They'd still have to pat the VATican; or did mean a Paypal doll?

Marco
04-02-2010, 09:02
:lol: :eyebrows:

Marco.

Marco
04-02-2010, 10:00
Hi Ali,


Ok,exactly how are the rods connected in your system Marco?


I've just been thinking about this again, and I thought that I would reverse the question for the benefit of people thinking about doing this.

How would you do it if you were connecting the earth rods in Steve's set-up? If you explain the procedure you'd advise then we'll put it to the electrician when he does the job and then see what he says... Others can also feel free to chip in with their thoughts here too :)

Marco.

Ali Tait
04-02-2010, 10:11
Not sure at all how I'd do this Marco,that's why I was interested in how yours was done.I find it difficult to see how it could be done both within the regs and to avoid the safety issues I mentioned.Can you ask your leccy mate?

Marco
04-02-2010, 10:23
Will do, mate :)

Could you just briefly outline again what you see as the potential problems and I'll put those to him.

Marco.

John
04-02-2010, 10:49
When I was upgrading my mains I looked into this and got scared by the potential issues
Ali mentioned
If i remember correctly a fault in the earth could mean that all the local household earths could be passing a massive voltage in your system with potential fatel consequences
I would imagine the safety regs would cover any potential issues and as long as your electrician follows them then it should be safe but its really best to fully check into this

John
04-02-2010, 10:55
Read this arcticle
http://www.acoustica.org.uk/t/earth.html

Marco
04-02-2010, 10:59
Hi John,


I would imagine the safety regs would cover any potential issues and as long as your electrician follows them then it should be safe but its really best to fully check into this...


I fully agree on both points and Steve and I will do so accordingly. Thanks for posting that link - most informative :)

Marco.

Dave Hewitt
04-02-2010, 11:18
Hi
Marco,As suggested earlier by Dave Cawley I think the issue only applies if your mains supply is pme connected and special conditions apply if so.Ithink under certain fault conditions ie neutral conductor break if your earth system is the least impedance in the area then you could get massive current flowing through earth devices causing overload and possible overheating and fire.I think Steves installation wont be connected this way,but easiest way out is to ask the supplier.As Ali states this would probably never happen,but could.I think the pme system was introduced to reduce cost by removing the earth conductor which was in effect in parralell with the neutral conductor,so it may be possible that this system only was used after acertain date and therefore installations before then are not affected.If we could find out if this is so it would save us all alot of hassle and we could sleep easier knowing we wont get blown out of bed if someone puts an airpick through a mains cable in our neighbourhood.I also have a large 845 Marco if your interested.
Dave.

Dave Cawley
04-02-2010, 13:38
Even without a fault, PME and an additional earth stake will give undesirable earth currents. Unless as I said you only use the earth stakes for the Hi Fi spur and diss the PME earth on that spur. I'm not sure this is legal though?

Regards

Dave

Ali Tait
04-02-2010, 18:04
That's the point I was trying to make Dave.Marco,can you find out if that is indeed the case? The concerns I have about the spike connected to the house earth is what's outlined in that link John posted.Can you show that to your mate?

Barry
04-02-2010, 18:07
I have been following this lively (and at times heated) discussion with some interest. Whilst I am still to be convinced that the minimisation of the source impedance is an essential requirement (although AnthonyTD’s argument goes some of the way), I have, out of curiosity, measured the quality of the mains supply in my own house.

I measured the following values at two locations: at a wall socket in the kitchen (known to be a spur from the ring main) and at the wall socket that feeds the distribution strip of my audio system. The measurements are as follows:

Kitchen wall socket (on a spur)

Off load voltage: 242.7V
Source resistance: 0.21Ω
Neutral – Earth potential difference: 0.25V (AC), 0V (DC)
Neutral – Earth loop resistance: < 0.3Ω


Living room socket (on the ring)

Off load voltage: 241.5V
Source resistance: 0.24Ω
Neutral – Earth potential difference 0.5V (AC), 0V (DC)
Neutral – Earth loop resistance: < 0.2Ω

My house was built in the early ‘60s. As far as I know it does not use a PME system; the earth continuity conductor from the house wiring is connected to the metal armouring of the incoming supply cable.

I have no idea if the above measured values are good or not. I cannot say I have noticed any change in audio quality in changing from a modest Duraplug 4-way distribution board with 14 contacts/connections in the mains circuit and a loop resistance of 0.5Ω, to an Olsen 6-way distribution board with 22 contact/connections (it is fitted with a Schaffner capacitor block) and a loop resistance of 0.3Ω.

Again I can understand to some extent the desirability of low source impedance, but I do not understand how having a low earth impedance helps, when under normal conditions no current will flow to earth.

Perhaps some AoS members who are involved in the electricity supply business can explain.

Regards

Ali Tait
04-02-2010, 18:31
Not sure either Barry,but all who have tried it say it's made things better.One thing no-one has mentioned is d.c. offset.This can have a deleterious effect on sound.Has anyone measured theirs?

Barry
04-02-2010, 18:39
Hi Ali,

I wanted to measure this but would need a scope to distinguish between the 240V ac from any DC offset.

What is an acceptable value for the source impedance? And what is an acceptable value for the earth loop impedance? For the latter, I have seen an IEE value of < 8 Ohm for circuits supplying 6A.

Are the values I measured acceptable?

Regards

Ali Tait
04-02-2010, 18:40
Just done mine-At the IEC feeding my amp,d.c. is 0.014v (Fed via DIY mains filter) Straight out of a socket-4.74v.This house is three years old.How does others compare?

Ali Tait
04-02-2010, 18:41
Barry,if you have a meter,just set it to d.c. volts and measure?

Barry
04-02-2010, 18:47
Barry,if you have a meter,just set it to d.c. volts and measure?

Yes I have two: An HP E2373A digital multimeter and a good old Avo 8 (Mk V ?).

I assumed imposing an AC voltage on a meter set to DC would damage it, are you sure it's safe?

Regards

Ali Tait
04-02-2010, 18:58
Not sure about that but I've never had a problem.I have a Fluke.I guess if the meter is rated for it there will be no problem,the meter will just ignore the ac and give the dc reading.After all,if you are measuring the ac,there is still dc present!

Barry
04-02-2010, 19:08
Thanks Ali,

I'll give it a go.

Regards

swampy
04-02-2010, 19:12
You may all find this useful reading.

http://sound.westhost.com/articles/xfmr-dc.htm#dc1

At one time Brian over at DiyHS sold a small, cheap and simple DC mains blocker, not sure if he still does. If you use a mains filter with a tx output then DC is obviously blocked by the filter.

Ali Tait
04-02-2010, 19:14
Dave,it's your design of filter I'm using! :)

Ali Tait
04-02-2010, 19:15
....And it's doing a very good job of getting rid of the dc.

Beechwoods
04-02-2010, 19:15
Yes I have two: An HP E2373A digital multimeter and a good old Avo 8 (Mk V ?).

I assumed imposing an AC voltage on a meter set to DC would damage it, are you sure it's safe?

Regards

My cheapo Maplin multimeter would freak out at an AC signal when it was set to measure DC so I'd be tempted to exercise caution, especially if you only have the one multimeter, or a nice antique (I assume the AVO is slightly antique. My dad's was; Bakelite and all :))

Ali Tait
04-02-2010, 19:29
No problem with my Fluke.

Mike
04-02-2010, 19:50
I can understand to some extent the desirability of low source impedance, but I do not understand how having a low earth impedance helps, when under normal conditions no current will flow to earth.

Ditto! :scratch:

CornishPasty
04-02-2010, 22:31
Read this arcticle
http://www.acoustica.org.uk/t/earth.html


I've already told you the same thing in post 2.

The Grand Wazoo
04-02-2010, 22:32
My cheapo Maplin multimeter would freak out at an AC signal when it was set to measure DC so I'd be tempted to exercise caution,

Please folks, if you've read the above posts & it tempts you to try, listen carefully:

If you don't know what you're doing you shouldn't do it

I don't want to see anyone else posting 'From The Grave' please - that's my job.

Dave Cawley
04-02-2010, 22:43
Guys, please!

Putting AC into a DC voltmeter won't cause any harm at all.

But grounding a PME system with earth rods probably will. I think we all want to know, 1) does Steve and Marco have PME ? 2) are they connected or isolated from the PME ground? and 3) what does the qualified electrician have to say about this?

It must be quite simple? I expect we are missing something, time to spill the beans so we can all sleep soundly!

Regards

Dave

Barry
04-02-2010, 22:53
Guys, please!

Putting AC into a DC voltmeter won't cause any harm at all.

But grounding a PME system with earth rods probably will. I think we all want to know, 1) does Steve and Marco have PME ? 2) are they connected or isolated from the PME ground? and 3) what does the qualified electrician have to say about this?

It must be quite simple? I expect we are missing something, time to spill the beans so we can all sleep soundly!

Regards

Dave

I've had a look at the instructions for both my meters, the HP and the Avo, and nowhere does it warn against putting AC into the meter when set on a DC range, so I guess that confirms both what you and Ali say. If it doesn't work, will you buy me a repalcement? ;)


Please folks, if you've read the above posts & it tempts you to try, listen carefully:

If you don't know what you're doing you shouldn't do it

Rest assured Chris, I took very great care during the measurements.

I still don't know if they're acceptable values - but then if they're not, it gives me something else to worry about!

Regards

CornishPasty
04-02-2010, 23:01
Dave, it's very simple. It doesn't matter whether you sink an earth rod, a water pipe, a gas pipe, structural steelwork or whatever, it must be bonded back to the main earth with a suitably sized conductor. As long as you do that, if there is an earth fault any conductive parts will rise to the same potential or thereabouts. There may be some slight difference in potential between two conductive parts but it won't be great enough to cause harm.

Joe
04-02-2010, 23:16
If you don't know what you're doing you shouldn't do it



Life basically consists of doing things you don't know about. In Lou Reed's phrase: 'It's like trying to teach a pony Sanskrit'.

Barry
04-02-2010, 23:29
I've just measured the DC on my mains supply: 18mV. Nothing to worry about then!

Regards

The Grand Wazoo
05-02-2010, 00:34
Rest assured Chris, I took very great care during the measurements.


We have to remember that these conversations stay here long after we've forgotten them. I feel sure that those who're currently engaged in the discussion do know what they're doing.
However, someone else may read this tomorrow, next year or whenever & decide to stick some meter probes where they really do not belong.

I don't think any of us would like to feel we might be responsible for that.

Marco
05-02-2010, 07:21
You're quite right to give that warning, Chris :)

Sorry I wasn't around last night, chaps, but Ian Walker came round for a sesh and brought round the latest top notch Croft preamp (25R) for a listen, along with a World Designs preamp and PSU, so I was otherwise engaged.....

I've read what's been written and for me Ralph hits the nail on the head:


Dave, it's very simple. It doesn't matter whether you sink an earth rod, a water pipe, a gas pipe, structural steelwork or whatever, it must be bonded back to the main earth with a suitably sized conductor. As long as you do that, if there is an earth fault any conductive parts will rise to the same potential or thereabouts.


That's what we'll be suggesting to Matt (our electrician) - it seems the safest way of doing things :cool:

Marco.

Dave Cawley
05-02-2010, 08:36
Hi Marco

But will that produce an additional earth current, and is this what you really want for Hi Fi ?

Dave

Marco
05-02-2010, 08:46
I'm not sure, Dave - the only way we're going to find out is to listen... Also, the electrician may have a better alternative suggestion which is still as safe.

We'll keep everyone posted on the outcome after the spark's been tomorrow :)

Marco.

Dave Cawley
05-02-2010, 09:19
OK, could you ask him if you and Steve have PME please? This is important for the rest of us to know.

Thanks

Dave

Marco
05-02-2010, 09:26
No worries - will do :)

Marco.

Ali Tait
05-02-2010, 10:09
Indeed.I'll be interested in the outcome also.If possible,try different ways and see if it makes any sonic difference.

bonneville
05-02-2010, 11:10
Hi One quick question that has always puzzled me.How does earthing the gas pipe create a connection when new supply pipes up to the house are all plastic.

Vinnie

Dave Hewitt
05-02-2010, 11:23
Hi Vin
It does'nt,but the pipes in your house are bonded together to the electrical earth.
Dave.

bonneville
05-02-2010, 11:45
Hi Dave
So the earth wire at the meter is to earth the gas pipe throughout the house rather than be a route to earth its'self?

Vin.

Dave Hewitt
05-02-2010, 11:56
Hi Vin
Yes it keeps all exposed metal work at earth potential so in theory they cant become live if a fault occurs.
Dave.

Mike Reed
05-02-2010, 12:31
I would also be interested in finding out the safest way of connecting (an) earth rod(s), because I read somewhere that if it is connected in isolation ( I imagine that means without any bonding earth at the consumer unit end, but I'm not sure) there is a potential danger.

My installation is fully earth connected at the consumer unit end, which is close to the mains fuse; this was re rigeur, according to my electrician.

However, my rod comes in close to, and is connected to, each of my T & E terminations at the hifi end.

My electrician didn't have a problem with that, as it was already bonded, but it would be nice to put this unknown potential problem to bed.

My friend, who lectures in Physics and whose friend is a qualified electrician, has a similar installation, but is not at all concerned.

Earthing theory and safety practice is, to me, a more arcane branch of electrics.

Ali Tait
05-02-2010, 13:45
Hi Dave
So the earth wire at the meter is to earth the gas pipe throughout the house rather than be a route to earth its'self?

Vin.

It's to keep you safe Vinnie,you wouldn't want your radiators live at 240v!

Filterlab
05-02-2010, 14:25
All the objectionable flannel aside, the result is as such:

ALL electrical work was undertaken by a qualified electrician.
The cost was pennies (given the overall cost of Steve's system).
Improvements in sound quality are evident to the ears of those who'll be listening to the system, and that surely is the point of the exercise.

Excellent stuff. :)

Dave Cawley
05-02-2010, 14:28
Hi Rob

Yes and no. The earth stakes are not yet fitted, and we are woried about the PME aspect.

Dave

Filterlab
05-02-2010, 14:32
Hi Rob

Yes and no. The earth stakes are not yet fitted, and we are woried about the PME aspect.

Dave

Hey Dave.

Which bit's yes and which bit's no?

:)

**EDIT** Oooh, I see what you mean about the PME issue, reading that linked article it sounds like it could cause some problems.

Ali Tait
05-02-2010, 15:12
Indeed.I have no objections to this bar the safety and legal aspects,and I'd like to try it myself.My overriding concern is the safety of all though.

Steve Toy
05-02-2010, 16:50
If it's not safe and legal it won't be happening.

I'm the one who has fused plugs throughout.

anthonyTD
05-02-2010, 17:31
hi all,
if you run your hi fi system from the incoming mains but do not use the incoming mains earth and instead use an earth that is seperately grounded in your garden for example, then in theory if there was a fault on the mains earth system [incoming from the street] then it is posible with some equipment that the fault could find its way through your system and to the grounding rod grounding your system, this as others have quite rightly pointed out [ali etc] could potentialy lead to your grounding rod trying to ground huge amounts of current hence there is a real concern here, on the other hand if you want to fit a dedicated earth rod near your system then IMHO it should be bonded to your existing incoming mains earth. the affect the new earth rod will have on your system will depend on a few things, ie; how far away the original earth rod [or incoming earth] is from your system, and also how good the original earth was to begin with.
hope this helps.:)
regards,anthony,TD...

Dave Hewitt
05-02-2010, 17:46
Hi All
Something I often wondered about,does equipment that does not have a mains connection as such,ie my marantz cd player if connected to another two pin connected device,does the panel have aview as to whether a cd player with earth would sound better.
Dave.

Marco
05-02-2010, 18:06
Hi Anthony,

Your last post pretty much sums up my current feelings on the matter, and I'm sure Steve will feel the same.


the affect the new earth rod will have on your system will depend on a few things, ie; how far away the original earth rod [or incoming earth] is from your system


Interesting...

So are the earth rods better as near as possible to the system or as far away as possible? :)

Marco.

Dave Hewitt
05-02-2010, 18:11
Marco
The earth rods should be as close as possible and bondedto your incoming mains earth,but you still have the problem regarding pme system or not.
Dave.

Barry
05-02-2010, 18:13
We have to remember that these conversations stay here long after we've forgotten them. I feel sure that those who're currently engaged in the discussion do know what they're doing.
However, someone else may read this tomorrow, next year or whenever & decide to stick some meter probes where they really do not belong.

I don't think any of us would like to feel we might be responsible for that.

Chris,

I’m not sure what you are trying to say here. Are you objecting to my post describing the measurements I made on the mains supply to my house as encouraging others to follow suit and undertake a potential dangerous activity?

In my post I will admit that I did not describe how I measured the source impedance; simply inserting the probes of a multimeter set to measure resistance into a wall socket will not work and is guaranteed to destroy the meter and possibly injure anyone doing such.

I have already stated my opinion that any modification of the mains supply and of the earthing arrangements should not be undertaken lightly and the consequence of adding supplementary earth spikes considered very carefully.

If the Moderators feel that I have been irresponsible in making these posts, they can delete them, as is their prerogative.

Regards

anthonyTD
05-02-2010, 18:19
Hi Anthony,

Your last post pretty much sums up my current feelings on the matter, and I'm sure Steve will feel the same.



Interesting...


So are the earth rods better as near as possible to the system or as far away as possible? :)

Marco.
hi marco,
near as posible, and in good salted, moist earth!
A...

Marco
05-02-2010, 18:35
Ok, noted :)

Toyster, did you hear that? Eat a jumbo-sized bag of 'Salt & Shake' and have a good pish on the lawn before I get there!! :eyebrows:

http://img697.imageshack.us/img697/4351/1044v.gif (http://img697.imageshack.us/i/1044v.gif/)

Marco.

Ian Walker
05-02-2010, 20:06
Well guys ive just disconnected my earth rods in the garden and returned to the incoming mains earth only and guess what, it sounds better to me.
Work that one out?.

Ian.:scratch:

Mike Reed
05-02-2010, 20:13
Marco
The earth rods should be as close as possible and bondedto your incoming mains earth,but you still have the problem regarding pme system or not.
Dave.

Close as possible TO WHAT, may I ask?

ANTHONY T D suggests as close as poss. TO THE EQUIPMENT (which suits me), but certainly in my case the rod cannot be bonded to the incoming mains earth. Of course it IS connected, not by bonding but by the earth wire in the individual cables (hard-wired; would this be classed as 'bonded'?)

'PROBLEM REGARDING PME SYSTEM OR NOT' Can you elaborate, as this is not understood? Thanks

Dave Hewitt
05-02-2010, 20:22
Hi
As close as pos to mains earth as stated,we dont have to drag all previous posts up again do we?
Dave

The Grand Wazoo
05-02-2010, 20:26
Chris,

I’m not sure what you are trying to say here. Are you objecting to my post describing the measurements I made on the mains supply to my house as encouraging others to follow suit and undertake a potential dangerous activity?


No Barry,
Sorry I didn't mean to infer anything about any individual. I just had a vision of someone reading the thread & with no knowledge of what they were doing at all, deciding that they must know what their circuit measures (there was talk of a comparison to see who had the lowest figure, I think) & doing themselves some damage. As I said all concerned seemed to know what they were talking about, but later readers may not. It's those others who the 'if you don't know what you're doing you shouldn't do it' comment was aimed at.

Barry
05-02-2010, 21:05
No Barry,
Sorry I didn't mean to infer anything about any individual. I just had a vision of someone reading the thread & with no knowledge of what they were doing at all, deciding that they must know what their circuit measures (there was talk of a comparison to see who had the lowest figure, I think) & doing themselves some damage. As I said all concerned seemed to know what they were talking about, but later readers may not. It's those others who the if you don't know what you're doing you should do it comment was aimed at.

Hi Chris.

I misunderstood the tone of your post; a potential problem with written text. :doh: I guess I was just feeling a bit sensitive. Message now understood.
Regards

anthonyTD
05-02-2010, 21:06
hi all,
as chris and others have stated the information and ideas talked about in this thread are just that, anyone interested in what has been written here should first consult a qualified electrician who is up to date on the latest legislations etc, then on his/her strict recomendations and only then should you consider implimenting any or all of the ideas put forward in this thread.
A...

Dave Cawley
05-02-2010, 21:14
Wow! big text man.........

Dave

Steve Toy
05-02-2010, 21:22
Indeed Dave. Do you have a problem with that?

anthonyTD
05-02-2010, 21:25
Wow! big text man.........

Dave
:stalks::eek:;):)
A...

Mike Reed
06-02-2010, 10:57
Hi
As close as pos to mains earth as stated,we dont have to drag all previous posts up again do we?
Dave


Then it appears that you and Anthony have differing opinions; either it's more beneficial to have the earth rod connected close to the kit or close to the incoming mains earth bonding. Sometimes this can be one and the same thing, but not in my, and others' cases.

DAVE, there are two parallel threads on Steven's mains installation; here and P.F. Each runs to many pages with its concomitant diverse opinions, comments and disagreements. If I've missed an explanation of P.M.E., I apologise, but I as freely give when relevant, I rather expect advice from those better acquainted with a topic than I, so to be 'referred to drawer' isn't that helpful, I'm afraid.

After installing, or having had installed, dedicated mains circuits for twenty-five years, I am pleasantly surprised, if a little bemused, that this subject seems all the rage nowadays. I wonder if Roy Riches is aware of this, after making this his hobby-horse for just about as long.

DSJR
06-02-2010, 12:20
Surely getting your main earth attachment to the (copper?) pipes as they come into the house is reasonably all you need, as the pipes are buried in the ground considerably longer than a plain old copper rod... may be different in our case as the incoming pipe is lead, due to the age of the building.

Joe
06-02-2010, 12:41
Indeed Dave. Do you have a problem with that?

WHAT???

Dave Hewitt
06-02-2010, 14:33
Hi Mike
Sorry if I seemed abrupt but it appears that some of the previous posts are just tongue in cheek and are not really being helpfull to Steve or anyone who is genuinly interested in safety.In my experience earth rods should be as near as possible to mains earth if its feasible, thus keeping cables short and resistance low.
Regards Dave.

Ali Tait
06-02-2010, 15:09
Aye,but isn't the point of this to provide a low impedance earth for your system? In which case it would make sense to have the rods as near the system as possible,in order to provide an "earthier" earth if you see what I mean.

DSJR
06-02-2010, 15:36
I think we're talking tiny fractions of an ohm here aren't we? I was hauled over the coals this morning on another forum for even daring to suggest that the reason the Naim mains lead *may* have a difference over the standard one is its 37A rating - higher than the ring main actually. I was told in no uncertain terms that the difference of a metre wire of this margin over the house mains wiring itself may be around 0.02 ohm and that this is totally irrelevant to an amplifier.....

It may just be that Steve would have found an improvement just by cleaning the large supply fuse on its own if it was so crunged up.......

Ali Tait
06-02-2010, 15:45
Maybe so.I'm interested in what effects(if any) the earth spike has though

Macca
06-02-2010, 15:52
When it comes to electricity I can rewire a plug and that's it. That given, would somone explain why cleaning a fuse would make a difference? Note I'm not disputing that it can, but asking if there is any rational scientific theory that explains why it can.

DSJR
06-02-2010, 16:01
Increased resistance due to corrosion of the contacts....

HiFi dave's just told me about changing the magnetic steel screw in an MK Tough-Plug for a non-magnetic stainless steel one...... - oh dear, here we go again - and I've already lost the tiny bit of credibility I had on HDD's forum...............................

Ali Tait
06-02-2010, 16:17
Try cleaning your plugs with Brasso...

Macca
06-02-2010, 16:19
Increased resistance due to corrosion of the contacts....
......

Hmmm... Okay, Dave - I'll buy that:)

Macca
06-02-2010, 16:45
Try cleaning your plugs with Brasso...

I've done the Brasso thing with the plugs a long time back but could not hear a difference -- system not 'up to it', possibly...

anthonyTD
06-02-2010, 16:53
Aye,but isn't the point of this to provide a low impedance earth for your system? In which case it would make sense to have the rods as near the system as possible,in order to provide an "earthier" earth if you see what I mean.

guys,
as ali said above all we are trying to acomplish is the lowest posible earth potential, hence fitting an earth rod closer to your system may indeed bring benefits if the original earth system [incoming mains or original earth rod etc] is a long way from the points or spur your using your system from.
as for relying on the incoming water pipe as a good earth, thats fine, but most new houses and modified ones have a plastic pipe coming in from the road hence it is obviously of no use as an earth now.
and as stated in an earlier thread any new earth that is fitted should still be bonded to the original incoming mains earth.
A...

Kris
06-02-2010, 17:24
Fascinating subject.

2 Interesting links for your perusal: http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=25383
and

http://en.wikipedia.org/wiki/Ground_%28electricity%29

Kris.

Barry
06-02-2010, 19:37
Increased resistance due to corrosion of the contacts....

HiFi dave's just told me about changing the magnetic steel screw in an MK Tough-Plug for a non-magnetic stainless steel one...... - oh dear, here we go again - and I've already lost the tiny bit of credibility I had on HDD's forum...............................

For goodness sake!

That's about as likely to make as much difference as replacing the cable from one using the old colour code to one that uses the new.

Regards

Marco
06-02-2010, 22:17
Well, chaps, installing the earth rods in Steve's system was a HUGE success, both in terms of the safety aspect and also very dramatic sonic improvements! :)

Don't have time to go into detail now, but I'm sure Steve will be along to add his thoughts later :cool:

Marco.

Dave Cawley
06-02-2010, 23:02
And PME on both systems?

Dave

Marco
06-02-2010, 23:32
Hi Dave,

Just flitting in and out at the moment.... No, Steve didn't have PME. We thus fitted the earth rods which were bonded to his existing house earth, and the results were, well..... :eek: :eek: :stalks: :wow:

Laters!

Marco.

Themis
07-02-2010, 07:32
oh dear, here we go again - and I've already lost the tiny bit of credibility I had on HDD's forum...............................
If you're like me, then credibility is only a side-effect. ;)

John
07-02-2010, 08:45
I given up on creditabilty a long time ago:lolsign:

Primalsea
07-02-2010, 11:48
The general idea of using earth rods is not so much to lower earth impedance for your mains supply but to lower it for higher frequency noise. The usual system for filtering non common mode noise is to dump it on the earth line. The lower impedance your earth is the more noise can be successfully dumped without it polluting the earth's of other equipment.

For mains power no current should flow in your earth line unless there is a problem. RCD's monitor the imbalance of current flowing in the live and neutral lines. The idea is the same current flowing in the live line should be the same as that flowing in the neutral. If there is a difference it means there's a short somewhere, hopefully to earth but sometimes to another potential via a person, ouch!

I think the definitive answer on this would come not from a general electrician but one who installs Electron Microscopes as they need a clean mains supply and have to be situated in completely shielded rooms. Anyone know one?

Marco
07-02-2010, 11:59
Hi Paul,

You're on the ball again (as usual!) :)


The general idea of using earth rods is not so much to lower earth impedance for your mains supply but to lower it for higher frequency noise. The usual system for filtering non common mode noise is to dump it on the earth line. The lower impedance your earth is the more noise can be successfully dumped without it polluting the earth's of other equipment.


That is *precisely* what's happened in Steve's system and, bloody hell, I've rarely heard such a fundamental improvement, musically, in all my years experimenting with hi-fi gear! :eek:

Going out now to vist a mate for a music sesh, so will comment in detail later. The Toyster must still be in bed after listening to choons long into the early hours in the morning after his taxi shift! :eyebrows:

Marco.

Primalsea
07-02-2010, 12:25
Hi Paul,

You're on the ball again (as usual!) :)

Marco.

These days Marco I mostly feel as if I'm off my rocker, never mind on the ball!

Kris
07-02-2010, 12:42
Electron Microscopes as they need a clean mains supply and have to be situated in completely shielded rooms

Opposing magnet flywheel regeneration? :scratch: :confused:

Steve Toy
07-02-2010, 13:08
I went straight to bed after work. It was 4 am and Tasha would not appreciate being woken up.

spendorman
07-02-2010, 18:47
The general idea of using earth rods is not so much to lower earth impedance for your mains supply but to lower it for higher frequency noise. The usual system for filtering non common mode noise is to dump it on the earth line. The lower impedance your earth is the more noise can be successfully dumped without it polluting the earth's of other equipment.

For mains power no current should flow in your earth line unless there is a problem. RCD's monitor the imbalance of current flowing in the live and neutral lines. The idea is the same current flowing in the live line should be the same as that flowing in the neutral. If there is a difference it means there's a short somewhere, hopefully to earth but sometimes to another potential via a person, ouch!

I think the definitive answer on this would come not from a general electrician but one who installs Electron Microscopes as they need a clean mains supply and have to be situated in completely shielded rooms. Anyone know one?

I was responsible for all the equipment in several labs, one piece of which was an electron microscope. It was not in a shielded room, nor on a specially filtered mains supply. However we were not using it on its most sensitive settings. Just as well as there was some vacuum equipment nearby that used a 3KW RF generator.

Primalsea
07-02-2010, 19:34
I think some don't have special requirements as you say (maybe due to age or resolution). I know of one company that bought a 2nd hand unit from a university and installed it in the back of a warehouse! I would have thought that an installation engineer would have had their fair share of ones that do have special supply requirements though.

spendorman
07-02-2010, 20:03
I think some don't have special requirements as you say (maybe due to age or resolution). I know of one company that bought a 2nd hand unit from a university and installed it in the back of a warehouse! I would have thought that an installation engineer would have had their fair share of ones that do have special supply requirements though.

Yep, ours was bought second hand from a university! Was put in a clean room environment though.

Joe
07-02-2010, 23:07
Increased resistance due to corrosion of the contacts....

HiFi dave's just told me about changing the magnetic steel screw in an MK Tough-Plug for a non-magnetic stainless steel one...... - oh dear, here we go again - and I've already lost the tiny bit of credibility I had on HDD's forum...............................

I can't be doing with any of that, but loss of 'credibility' in the eyes of a bunch of spods on a hifi forum is not something to lose sleep over.

Marco
08-02-2010, 09:17
Have you read some of the blinkered thread crapping being written by the idiot 'usual suspects' on the discussion running concurrently on pfm? I know what I'd love to do with some of them! :rolleyes: :wanker:

Marco.

Dave Hewitt
08-02-2010, 10:40
Hi
Even tho all the posts on pfm can probably be backed up with theory and measurement the end result cant be predetermined as I discovered once when I replaced a Sony 700es amp with a Leak stereo 20, the Leak had afar worse paper spec but blitzed the Sony.So if I were Steve i'd be quite content with my mods which have proven to be safe and within the regs.
Dave.

Marco
08-02-2010, 12:17
I've no problem at all with that, Dave, and you're quite right :)

What I have a MAJOR problem with, however, (and indeed was a primary reason for me wanting to start up AOS to get away from all that crap) is people rudely insinuating that you're "imagining" things, simply because you're unable to provide (measurable) 'scientific proof' to confirm your genuine subjective experiences! :rolleyes:

It's simply a gross insult to one's intelligence. The FACT is not every effect genuinely heard in audio can currently be 'proven' through measurement. If anyone thinks otherwise then *they* are the ones who are deluded!

Steve was only outlining the most plausible theory he could think of (which Paul has already alluded to here) to help explain the effect both him and I genuinely heard from installing his earth rods, and was then unfairly subjected to personal abuse (why on earth does someone's profession have to be brought into the argument??) by a couple of known idiots with an axe to grind. Of course it's right to challenge someone's observations if you feel what they're writing is incorrect - but do so in a way which shows some respect for the other person - always play the ball, not the man!

I do like pfm, but the mods there (and to an extent, Tony) let some people away with murder. I'd honestly love to line some of the tossers posting on that thread up against a wall and give them a right good slap. No wonder now the likes of ZG is a graveyard with characters like that populating forums, as people are scared to open their mouths and share their valid experiences for fear of being ridiculed.

Thank God that we have this friendly and peaceful sanctuary in which to discuss such legitimate audio topics where people (and their equally valid opinions) are automatically treated with the respect and courtesy they deserve.

Marco.

Ali Tait
08-02-2010, 13:11
It's just words on a screen Marco.Who cares? You shouldn't let it get to you.People will think what they want to think,it's pointless trying to change other's minds.They think you are just as deluded as you think they are! Why worry about it?

Ali Tait
08-02-2010, 13:13
In any case,if the upshot of fitting the spikes has been a reduction in rf hash,with the right equipment,this would be easily measureable.

Marco
08-02-2010, 13:29
Hi Ali,


It's just words on a screen Marco.Who cares? You shouldn't let it get to you.People will think what they want to think,it's pointless trying to change other's minds.They think you are just as deluded as you think they are! Why worry about it?

Oh I most certainly don't worry about (far from it) - it just angers me that some people have this blinkered, disrespectful attitude and you would seriously wonder if they'd have the balls to address you in person with such rudeness. In fact, I think some of them would benefit from being taught some manners! As for it being "just words on a page", I understand where you're coming from, but I strongly disagree.

I care and see it as much more than that, simply because I treat people (and expect to be treated the same way in return) 'on-line', as it were, the same as I would do in real life - so in effect there's nothing I would write here that I would not also say to someone in person. I always automatically treat my fellow man with due respect as a human being unless they prove that they deserve otherwise.

In other words, if people respect me, then I respect them, but if they ignorantly treat me with disdain, then if I think it's justified, I will return the compliment - usually with interest ;)

Therefore it's not simply "just words on a page" - it's much more real than that, and in my mind no different from having a conversation with people face-to-face. The same rules regarding manners therefore should apply!


In any case,if the upshot of fitting the spikes has been a reduction in rf hash,with the right equipment,this would be easily measureable.


Well I'm 99% convinced that's the case, so what is "the right equipment" of which you speak? :)

I'd like to obtain it, carry out the necessary tests, and then shove the measured results (confirming Steve's and my subjective analysis) right up the flatulent chuffers of those blinkered tossers!! :upyours: :eyebrows:

Marco.

Macca
08-02-2010, 13:38
you would seriously wonder if they'd have the balls to address you in person with such rudeness.


They wouldn't. That's why they do it on t'internet instead. Some seriously frustrated types out there, I regret to say.

Barry
08-02-2010, 13:43
I've no problem at all with that, Dave.

What I have a MAJOR problem with, however, (and indeed was a primary reason for me wanting to start up AOS to get away from all that crap) is people rudely insinuating that you're "imagining" things, simply because you're unable to provide (measurable) 'scientific proof' to confirm your genuine subjective experiences! :rolleyes:

It's simply a gross insult to one's intelligence. The FACT is not every effect genuinely heard in audio can currently be 'proven' through measurement. If anyone thinks otherwise then *they* are the ones who are deluded!

Steve was only outlining the most plausible theory he could think of (which Paul has already alluded to here) to help explain the effect both him and I genuinely heard from installing his earth rods, and was then unfairly subjected to personal abuse (why on earth does someone's profession have to be brought into the argument??) by a couple of known idiots with an axe to grind. I do like pfm, but the mods there (and to an extent, Tony) let some people away with murder.

I'd honestly love to line some of the tossers posting on that thread up against a wall and give them a right good slap. No wonder now the likes of ZG is a graveyard with characters like that populating forums, as people are scared to open their mouths and share their valid experiences for fear of being ridiculed. Thank God that we have this friendly and peaceful sanctuary in which to discuss such legitimate audio topics where people (and their equally valid opinions) are automatically treated with due respect and courtesy.

Marco.

Marco,

Anyone who has made cautionary posts to this thread, has done so because they were concerned with the overall safety aspects in the fitting of supplementary earth spikes.

I would number myself amongst those who have been sceptical, however if you and Steve have noticed an improvement, then there is little argument; I for one would certainly not accuse you of mendacity. However being of a curious nature, can you describe exactly the improvements you hear?

I'm interested in the idea that these improvements come about by the 'earthing' of high frequency noise present on the mains supply. Are you able to tell us what kind of earthing arrangements have been provided by the local electricity supplier for both you and Steve? I would agree with Ali that if mains 'hash' has been reduced then this can be measured; not that you need to prove your case.

Regards

Marco
08-02-2010, 13:52
Hi Barry,

Excellent post - I'll get to it later, as I'm just about to run off and do some work (for a change, haha!) :)

However, just one observation regarding this:


Anyone who has made cautionary posts to this thread, has done so because they were concerned with the overall safety aspects in the fitting of supplementary earth spikes.


Be under no illusion that I have no problem with that whatsoever - it's very important that the safety aspects of carrying out this type of work are kept firmly to the fore.

Speak later :cool:

Marco.

DSJR
08-02-2010, 15:03
In the olden days of the sixties and early seventies, research would have been carried out as a mag article, measuring the rf content on the mains before and after. I reckon the mains was better then in any case...

Joe
08-02-2010, 15:43
... cue Hovis advert ...

Steve Toy
08-02-2010, 17:47
I posted the following over on the other side:



Why does every thread where a really cost effective tweak is recommended have to turn into a subjectivist/objectivist circular bunfight?

It is always the same few imbeciles who place their own egos above the potential musical enjoyment of others.
If those reading this thread were to believe the technical jobsworths like Tibbs they may well deny themselves the chance not only to vastly improve their music listening enjoyment for very little cost (earth rods cost about £20 plus half a day's labour for a qualified electrician to fit them and ensure they work safely in conjunction with existing earthing arrangements) but also the chance to ensure future component upgrades realise their full potential.

In a paper linked to on AOS Andy Weekes described the dedicated earth as improving the rhythmic capabilities of the system.
I apologise for not posting the link here but I am posting from my phone.
I described the earth rods as making the system sound more musical.
Rhthmic or musical, it's a question of semantics but it amounts to the same.

Would Tibbsy subject those with far greater technical knowledge than me to the same ad hominem ridicule and ssecondary school jeering as permitted by the mods, I wonder?

I have received private correspondence from people whose findings concur with mine, people who have conducted blind tests and who have greater technical knowledge than me. They won't post their findings here though out of fear of ridicule from the know-it-all empty vessels like Tibbs.

Tibbs, I suggest you restrict yourrself to your comfort zone of the DIY room and leave those of us with an open mind and genuine wish to advance our listening enjoyment in peace to share our positive experiences with others.

As well as doing nobody here any favours your stance is steeped in nothing more than condescending self importance.

__________________

That Tibbs bloke who doesn't use his real name (no surprises there).

Marco
08-02-2010, 18:25
Why does every thread where a really cost effective tweak is recommended have to turn into a subjectivist/objectivist circular bunfight?

It is always the same few imbeciles who place their own egos above the potential musical enjoyment of others.
If those reading this thread were to believe the technical jobsworths like Tibbs they may well deny themselves the chance not only to vastly improve their music listening enjoyment for very little cost (earth rods cost about £20 plus half a day's labour for a qualified electrician to fit them and ensure they work safely in conjunction with existing earthing arrangements) but also the chance to ensure future component upgrades realise their full potential.

In a paper linked to on AOS Andy Weekes described the dedicated earth as improving the rhythmic capabilities of the system.
I apologise for not posting the link here but I am posting from my phone.
I described the earth rods as making the system sound more musical.
Rhthmic or musical, it's a question of semantics but it amounts to the same.

Would Tibbsy subject those with far greater technical knowledge than me to the same ad hominem ridicule and ssecondary school jeering as permitted by the mods, I wonder?

I have received private correspondence from people whose findings concur with mine, people who have conducted blind tests and who have greater technical knowledge than me. They won't post their findings here though out of fear of ridicule from the know-it-all empty vessels like Tibbs.

Tibbs, I suggest you restrict yourrself to your comfort zone of the DIY room and leave those of us with an open mind and genuine wish to advance our listening enjoyment in peace to share our positive experiences with others.

As well as doing nobody here any favours your stance is steeped in nothing more than condescending self importance.


F*cking yee-hah, Steve, and well said!! :clap:

You have written nothing which was unwarranted - sometimes one has to stand up for oneself and put these people in their place. A few years ago you wouldn't have had the balls to write that ;)

Marco.

P.S Noticing James Jong's recent reply, I'd make the point that if Tibbs was "only challenging your pseudo-science" then why did he make it personal by bringing up your profession? These people always stoop to that level when they're in danger of losing the argument... There is no need for that whatsover - play the ball, not the man!

Themis
08-02-2010, 19:46
I remember the reactions about Mark's mains leads over there...
I won't go to read the details, as I have better ways of spending my time.

Some are certainly too harsh in this forum over there. Too harsh to be taken seriously, imho, in any case.

Stratmangler
08-02-2010, 20:01
So you don't feel bound by the AoS Ethos then?

Joe

Did you edit this, or did someone do it for you ?

Chris:scratch:

Primalsea
08-02-2010, 20:04
I read the thread on PFM, well most of it before I lost interest really. I would hazard a guess that you would need to measure the earth impedance at a range of radio frequencies to have any idea. Testing it at mains frequency will be of little use.

Joe
08-02-2010, 20:11
Joe

Did you edit this, or did someone do it for you ?

Chris:scratch:

Someone deleted one of my posts, so I posted that as a follow-up.

Marco
08-02-2010, 20:14
Hi Paul,


I would hazard a guess that you would need to measure the earth impedance at a range of radio frequencies to have any idea.


It would be interesting for someone with the necessary knowledge and apparatus to carry that out :)


I read the thread on PFM, well most of it before I lost interest really.

Sadly, I think the thread is destined to end only one way.

Marco.

Mike Reed
08-02-2010, 21:58
I remember the reactions about Mike's mains leads over there...
I won't go to read the details, as I have better ways of spending my time.

Some are certainly too harsh in this forum over there. Too harsh to be taken seriously, imho, in any case.

THIS Mike? Is my memory THAT bad??????? I've added to mains threads but never instigated one. Can't recall any rancour, Dimitri, so maybe it's another Mike.

That other thread did, latterly, produce some reliable data on different earths and PME etc. sufficient to make me think. I didn't really understand it, but it did make me think.............

Themis
09-02-2010, 07:38
THIS Mike? Is my memory THAT bad??????? I've added to mains threads but never instigated one. Can't recall any rancour, Dimitri, so maybe it's another Mike.

Mark's leads I meant, sorry Mike. Post corrected. :o

Steve Toy
09-02-2010, 17:37
If the separate mains supply (whatever we have to call it) lowered the impedance, made everything sound bigger, more dynamic and raised the system's headroom then the separate earth, rather than bring more of the same to the party instead brought more music. Instrumental and vocal nuance and texture improved, rythms and sub-rythms were laid bare and the bass had more authority, drive and was more articulate. This is the type of upgrade that digs more information off the disc and delivers more music.

You could say that the mains supply upgrade was a round-earth improvement but the earthing upgrade was definitely flat earth.

Before the earth rods were installed Marco swapped out my Williams Audio DAC for his Audiocom International Sony DAS R1. It did sound tidier, more refined and the bass seemed to go deeper and have more body but the improvement was subtle enough for me to live without.

When the earth rods were ready for use we swapped the Williams DAC back in and the improvement they made was siginificant enough to eclipse the benefit of Marco's better DAC. I sighed with relief. Perhaps I wouldn't need to upgrade or have my DAC modified after all.

Then Marco swapped his DAC back in....

Ali Tait
09-02-2010, 17:57
Sounds good Steve,might give this a go myself.I can get the earth rods for free from work!

Steve Toy
09-02-2010, 21:04
I guess you know what you're doing and your existing earthing arrangements will be safe to use in conjunction with a dedicated earth.

Mike
09-02-2010, 21:15
I've had one sitting in my garage for at least five years now... One day. Maybe.

Ali Tait
09-02-2010, 21:16
Yes indeed.When you have a 6 year old runnng around,no chances can be taken.

Steve Toy
09-02-2010, 21:24
Mike you need five. The earth lead comes out of your consumer unit to the centre rod then outwards to the other four.

That's how mine's been done.

Mike
09-02-2010, 21:37
Mike you need five. The earth lead comes out of your consumer unit to the centre rod then outwards to the other four.

That's how mine's been done.

Well it ain't how mines gonna be done... I have a better plan! ;)

Ali Tait
09-02-2010, 21:40
G'wan then,whatcha got in mind?

Mike
09-02-2010, 21:45
An earth mat.

Barry
09-02-2010, 22:03
An earth mat.

When I used to work for GEC-Marconi at their research labs, we had to design earthing arrangements for various radar systems. A popular arrangement was the 'earth mat'.

There used to be a book in the library there entitled 'Earthing Systems' that gave the analysis and calculation of the RF impedance (i.e. resistance and inductance) for various conductor arrangements: vertical rods, horizontal rods, star arrangements, daisy chain, plates, grid meshes etc. ...

Could do with that book now. Unfortunately the library there is now closed down and I think the books were donated to the local college; apparently the justification being cost saving (isn't it always?), and that (nearly) everything is available on-line. :doh:

Regards

Ali Tait
09-02-2010, 22:11
Substations are earthed with earth mats.The mats are tied to earth rods driven 5 deep into the ground.How are you planning to do yours Mike?

Mike
09-02-2010, 22:15
I'm a firm believer in earthing going back to a single point. ;)

I don't particularly like rods... they're usually just hammered straight down (sometimes with dire consequences) and folk regularly report how performance is improved by 'watering'. To my mind this is wrong!

An earth point should be located (IMHO) where the conductivity is consistently good. It should not need 'watering'! :doh:

Pointing the thing at the ground and just whaling on it till it's buried is asking for trouble. The hole should be dug down to a depth where the soil is always moist and the rod placed horizontally in the hole! A good few bucketfuls of crushed charcoal (conductive carbon) wouldn't do any harm either. Don't use salt... It'll rot the copper away really fast and probably kill every plant for yards around! ;)

Mike
09-02-2010, 22:17
Substations are earthed with earth mats.The mats are tied to earth rods driven 5 deep into the ground.How are you planning to do yours Mike?

A variation on that very priciple... I like to call it the "earth anchor"! :lolsign:

Mike
09-02-2010, 22:19
When I use to work for GEC-Marconi

Was that the site in Coventry, Barry?

Marco
09-02-2010, 22:32
I'm a firm believer in earthing going back to a single point. ;)

I don't particularly like rods... they're usually just hammered straight down (sometimes with dire consequences) and folk regularly report how performance is improved by 'watering'. To my mind this is wrong!

An earth point should be located (IMHO) where the conductivity is consistently good. It should not need 'watering'! :doh:

Pointing the thing at the ground and just whaling on it till it's buried is asking for trouble. The hole should be dug down to a depth where the soil is always moist and the rod placed horizontally in the hole! A good few bucketfuls of crushed charcoal (conductive carbon) wouldn't do any harm either. Don't use salt... It'll rot the copper away really fast and probably kill every plant for yards around! ;)

Sounds like a good plan, Mike. I'd be interested in your thoughts once it's done. The only 'problem' (and it may not prove to be such of course) by doing this, is that with a single rod you don't get the benefits of star-earthing.

I've no idea whether your method of installing a single rod outweighs the benefits of star-earthing with multiple rods or not, but I do know how effective the latter (star-earthing) is when applied in other areas of audio - and the benefits are considerable......

Does anyone fancy A/B-ing both earth rod set-ups to find out? :lolsign:

Marco.

Ali Tait
09-02-2010, 22:42
Star earthing in an amp just means bringing all the earths back to a single point.I'm not sure having five rods would offer much if any benefit over one.

Steve Toy
09-02-2010, 22:47
All I know is my system sounds f*cking amazing. I just need a bit more oomph in the bass from my DAC to enter trouser-flapping territory. I'm already at rubber ball stage.

Barry
09-02-2010, 23:04
Was that the site in Coventry, Barry?

No, the research labs were at Great Baddow, just outside Chelmsford in Essex. We did work for Marconi Radar in Chelmsford as well as at Leicester.

Actually when I say 'We', it was the Antennas department that did the earth mat design. My work was in the design of microwave components, especially filters that ended up in radar systems and microwave communication systems (e.g. BT)

I have been doing a bit of 'Googling'. There seems to be a fair bit on the design of earth mats to help you.

Regards

Barry
09-02-2010, 23:10
Sounds like a good plan, Mike. I'd be interested in your thoughts once it's done. The only 'problem' (and it may not prove to be such of course) by doing this, is that with a single rod you don't get the benefits of star-earthing.

I've no idea whether your method of installing a single rod outweighs the benefits of star-earthing with multiple rods or not, but I do know how effective the latter (star-earthing) is when applied in other areas of audio - and the benefits are considerable......

Does anyone fancy A/B-ing both earth rod set-ups to find out? :lolsign:

Marco.

I assume Mike was thinking of using several horizontal rods connected radial fashion like a star (e.g.*), the center connection being the earth connection taken back and used by the system.

Regards

Marco
09-02-2010, 23:12
Star earthing in an amp just means bringing all the earths back to a single point.I'm not sure having five rods would offer much if any benefit over one.

Yup, I was thinking more in the case of star-earthed mains distribution blocks. I've heard the difference star-earthing makes recently, compared to simply hard-wiring mains leads directly into MCBs and/or banks of sockets on the wall. Of course there is also the mechanical decoupling effect to consider, offered by the former arrangement over the latter...

In any case, the combined positive sonic effect of mechanical decoupling and star-earthing in the above application is indeed very significant - one can only surmise if the same effect would be achieved when applied to earth rods.

Marco.