View Full Version : Mains conditioner - home made as good as Isotek Aquarius
Dynamics
28-04-2017, 21:20
I just wondered if anyone is skilled enough on this forum to have ever tried to make their own mains conditioning power bar or seperates conditioning unit, similar to the isotek Aquarius. Or power bar like the isotek Sirius.
Looking at what goes into the Aquarius it's not much but I'm sure the order of items on the circuit and their tolerances and quality all play their part into making one product better than another. But much of what I hear (from electrical engineer friends) is you just need a filter and I'm always a bit dubious it will be as good. And also the hobbyists making these types of units have been making rather rudimentary ones, which again I'm dubious of being as good as the isotek.
But I've heard these isotek devices in demos against b and q power blocks, and they can make a very good difference to decent hi fi. The Aquarius made an exposure amp sound like a different one, in a test at the Bristol show.
Problem is they are £1500 and for what's inside ?
It strikes me therefore why a hobbyist electrical engineer and hi fi fan hasn't just tried to look at what's in these isotek devices and build a copy or similar, which I'm sure wouldn't be breaking any copyright. Have a bake off and compare it to a b and q bar, and sell them on forums. They could make a few quid and buy a nice case too.
I suppose this is is a bit of a selfish question for me as I'm in the market for something like an Aquarius, when I can, but paying £1500 for what it is, is hard to stomach.
http://cdn2.mos.techradar.futurecdn.net//Review%20images/Hi-Fi%20Choice/HFC%20330/HFC330.isotek.aquarius_anno-580-90.jpg
Here's some stuff from the Lampizator website which might be of interest.
http://www.lampizator.eu/AC%20FILTER/SILK/FILTER.HTML
http://www.lampizator.eu/Fikus/SILK_AC_FILTER.html
I suppose it depends on the cleanliness of the mains in your location but I've found mains filtering can make a huge difference.
But also, different filters suit different amps. There's always a trade off between noise reduction and squashed dynamics. I've found they can blunt leading edges which ruins rhythms.
The trick is getting the filter that suits your gear.
Dynamics
29-04-2017, 11:18
Here's some stuff from the Lampizator website which might be of interest.
http://www.lampizator.eu/AC%20FILTER/SILK/FILTER.HTML
http://www.lampizator.eu/Fikus/SILK_AC_FILTER.html
I suppose it depends on the cleanliness of the mains in your location but I've found mains filtering can make a huge difference.
But also, different filters suit different amps. There's always a trade off between noise reduction and squashed dynamics. I've found they can blunt leading edges which ruins rhythms.
The trick is getting the filter that suits your gear.
Thanks for the links, but these are exactly the types of sites I've seen. It's all very homemade looking.
I don't reckon it would cost much to design a circuit on a circuit board similar to that of the isoteks etc, and the components on it and have it made, also then buy a metal case and mount it on. If you know what you are doing as an engineer. Surely it can be done for less than £1500.
I think the reason why the isoteks are charging £1500 is because of all their marketing, factory costs. But if someone did it as a hobbyist engineer and had the circuit made, I doubt it would cost more than hundreds for the privilege. Surely?
hifinutt
29-04-2017, 13:40
i am sure you could do it for less than 1500 quid . sadly isotek stuff has gone up massively . i bought my sigmas over 10 years ago and its still brilliant. i paid a grand new with a 25 year warrenty and they cost a shed load more now
i have had 3 of their syncros with very good effect
the secret is to buy s/h now i think to save money
like this one , i had mine converted to schuco like this one
http://www.hifi-forsale.co.uk/moreinfo7.php?prod_title=Isotek_Titan_power_line_c onditioner&p=&prod_id=45130&q=isotek&offset=
RothwellAudio
29-04-2017, 14:33
I'm sure the order of items on the circuit and their tolerances and quality all play their part into making one product better than another. But much of what I hear (from electrical engineer friends) is you just need a filter and I'm always a bit dubious it will be as good. And also the hobbyists making these types of units have been making rather rudimentary ones, which again I'm dubious of being as good as the isotek.
Thanks for the links, but these are exactly the types of sites I've seen. It's all very homemade looking.
I don't reckon it would cost much to design a circuit on a circuit board similar to that of the isoteks etc, and the components on it and have it made, also then buy a metal case and mount it on.
Is your issue with the DIY filters that they won't perform as well as the Isotek or that they look homemade?
The link posted above to the lampizator page is a good one and the circuit is a pretty standard RFI filter, much like what will be in the Isotek. I have no doubt that a good DIY filter will perform as well as a commercial one. As for looking homemade, any piece of DIY audio can look terrible or look fabulous depending on how much effort the maker wants to put into the appearance. And as for it not costing much to design a circuit board, you're wrong - it can takes ages to design a circuit board and having them made can cost a lot of money in tooling costs and set-up charges. It's not worth doing for a one-off project.
Ali Tait
29-04-2017, 14:53
You could buy a balanced mains transformer from Airlink for under 300 quid.
The Aquarius made an exposure amp sound like a different one, in a test at the Bristol show.
Firstly, the mains at the Bristol show is very noisy - hotels circuits aren't great to start with - and then with every adjacent room full of electronic kit adding their own noise to the system. So a mains conditioner is going to make a significant difference in that environment.
However, I too was very impressed with the Isotek demo at the Bristol show about 3yrs ago. I went out and bought four Isotek mains cables, and was impressed with the difference they made to my system. I then bought a Isotek GII Vision (http://www.analogueseduction.net/mains-blocks/isotek-gii-vision-6-socket-mains-distribution-block.html) and was even more impressed. The noise floor dropped significantly - with silences became deeper and the spaces between instruments became more obvious. Those are high on my list of best purchases.
That said - I've got noisy mains. I work in IT and have a lot of computer equipment. Even worse, I use Ethernet over mains to get network connectivity to the far ends of my house. You may well have better mains in your house than I do. So you may well not get the improvement that I get. - So I'd strongly recommend trying before buying.
I have used filters, balanced mains etc. and had a custom balanced mains wired in for years. When I tried taking all the gubbins out I was surprised that I preferred the sound. Balanced mains is best used with a DC blocker as a universal solution, but nowadays I just have an industrial star grounded mains block.
Sent from my SM-G920F using Tapatalk
Is your issue with the DIY filters that they won't perform as well as the Isotek or that they look homemade?
The link posted above to the lampizator page is a good one and the circuit is a pretty standard RFI filter, much like what will be in the Isotek. I have no doubt that a good DIY filter will perform as well as a commercial one. As for looking homemade, any piece of DIY audio can look terrible or look fabulous depending on how much effort the maker wants to put into the appearance. And as for it not costing much to design a circuit board, you're wrong - it can takes ages to design a circuit board and having them made can cost a lot of money in tooling costs and set-up charges. It's not worth doing for a one-off project.
Agree - the Lampizator circuit described is near identical to the Schaffner FN 343-10-05 EMI filter unit fitted to my Olsen 6-way distribution strip. The values used in the Schaffner unit are as follows:
C1 = 100nF
C2,3 =2.2nF
L1 = 0.27uH
L2,3 = 0.4uH.
The VDR is replaced with a 1 MOhm resistor, with a separate VDR fitted outside the Schaffner unit.
They are inexpensive (< £40 each), so even if one used an individual filter unit for each power outlet, the total cost, for say a 6-way design, need be no more then £300.
Dynamics
29-04-2017, 21:43
Yes I agree the isotek stuff went up a shed load and the basic Polaris strip was £300, it's now £450. I've been looking at the 4/5 year old isol-8 minisub 2 which was £800 but some selling used for around £300-£400. The newest model is about £1k-£1300. I'm just peived at paying a lot for something that looks so simple from its components. If you google the isotek solus and see the picture of its inners, its really quite ridiculous it could be £800 ish.
The isol stuff is interesting as I was reading the founder of isotek, who designed the original isotek stuff, went on to start up isol and I don't think Keith martin at isotek is a designer, so maybe the isol stuff is better. But if I had to choose between the solus at £800 and the isol 8 minisub latest model around a grand, I'd go for the isol as it looks like it has much more gubbins in it 'to do a job', if you could say that.
I don't think the diy filters will perform as well as I'd think it's the total design that makes the difference, and its not possible just to say it's the filter on its own, if you look at the isotek Aquarius circuit and a home made one. And I'm no engineer but I suspect I'm right as a lot more goes into the isotek aqaurius circuit or isol minisub, than a filter I think. Id be worried the homemade jobbies using wooden boxes are a bit dodgy with fire risk etc.
I do think it comes down to how much noise their is and at Bristol a lot, but I live in a flat and I suspect I'm affected by all the other people in the block etc or if not my fridge, air conditioning system I have etc which are always on.
On reflection I can see it might cost a bit for a circuit being made but I doubt more than hundreds if you went to a Chinese firm. The circuit board in the Aquarius looks rediculously simple and you could even solder the components onto the board in right places too. I'm surprised someone hasn't tried to do this on the cheap as a one man band, or maybe a kit. Do Kits to compete with say the aqaurius exist?. They should do at a fraction of the cost.
hifinutt
30-04-2017, 04:22
you hear very little about isol but isotek have been bringing out some superb stuff and are pretty big now . as said before , i wish it was not so expensive .
when i had a puresound L10 i put the isotek syncro on it and you could really hear the change .
http://www.isoteksystems.com/why-isotek/
I think if I had issues with the mains I would go the whole hog and buy a regenerator. Expensive but should solve all problems.
Sceptical about the whole thing though, as you go to shows in hotels and there are systems that despite using power conditioners or even regenerators sound lousy, then you go to the next room and hear a system with no mains cleaning gubbins that sounds great.
If the problem is interference from other devices causing audible anomalies like clicks and pops then I agree steps need to be taken. But if it is just a desire for improved sound then improving the quality of the basic items of kit, or improving the matching thereof, is a better use for the money IMO.
Printed cct boards are really of benefit mainly with high density of small components, and prior to the increased complexity of cct design we have today, point to point wiring was the norm, and it has some advantages.
In an audio amp the components can be placed such as to reduce connection length and distance between components, and also reduce the risk of RF parasitics.
With a mains filter, which probably has only a few components it seems to me that a cct board will have to be thick and strong, and the components may well be heavy - large high current coils for eg..
Printed cct board layers are expensive if thick copper is required for high current reasons, but high current connections with stranded wires are easy to do and cheap.
Regarding looks, I would consider the old cast alloy boxes which I have used several times and produced fairly professional finishes with.
Dynamics
30-04-2017, 10:16
Printed cct boards are really of benefit mainly with high density of small components, and prior to the increased complexity of cct design we have today, point to point wiring was the norm, and it has some advantages.
In an audio amp the components can be placed such as to reduce connection length and distance between components, and also reduce the risk of RF parasitics.
With a mains filter, which probably has only a few components it seems to me that a cct board will have to be thick and strong, and the components may well be heavy - large high current coils for eg..
Printed cct board layers are expensive if thick copper is required for high current reasons, but high current connections with stranded wires are easy to do and cheap.
Regarding looks, I would consider the old cast alloy boxes which I have used several times and produced fairly professional finishes with.
Hi Dennis
Would you be experienced enough to help me try and build one?
Regards Simon
Power Inspired AG 1500. Regenerate rather than filter. I've run my entire system off one now for ages.
Power Inspired AG 1500. Regenerate rather than filter. I've run my entire system off one now for ages.
I use the smaller 500. Works well with me anyway.
I have used filters, balanced mains etc. and had a custom balanced mains wired in for years. When I tried taking all the gubbins out I was surprised that I preferred the sound. Balanced mains is best used with a DC blocker as a universal solution, but nowadays I just have an industrial star grounded mains block.
Sent from my SM-G920F using Tapatalk
That doesn't surprise me at all. My experience parallels your own in that all the mains conditioners, regenerators etc that I have heard have changed the sound but not actually improved it. Just as you, I just use a star wired mains block - no filtering etc.
Dynamics
30-04-2017, 15:27
I borrowed a star wired mains block from my dealer. It was a music works light, and it made damm all difference to my system when I had pmc twenty 23s at the time and my cyrus signature stuff.
Reading between the lines of what everyone who has said who has owned and used conditioners, I think there is a difference in a star wired block to something like the Aquarius which is in a different class.
I like the idea of regenerators but I don't think they deal with common and differential mode noise and the sine wave coming into most U.K. homes is decent as the power supply in the U.K. is good, so need of reconstruction often, but I know people who have said on forums using regenerators in noisy areas is a very good thing to do and gets good results, as with conditioners.
I certainly could help you Simon, but ATM have no familiarity with any ccts, but I have built three items in RS cast alloy boxes over the years. I would post some pics but it seems so convoluted, and I don't want my stuff posted on public 'profile' forums.
I'm sure there are some out there though
RothwellAudio
02-05-2017, 11:03
In my opinion equipment should be designed on the assumption that the mains is noisy rubbish of uncertain voltage. It should take steps to deal with it and make sure it works properly anyway. However, we have to live with things as they are, not things as we would like them to be. Probably the worst offenders for not dealing with poor mains are power amps. Most other things should be a lot more immune to noise on the mains.
BTW, what's a star wired mains block?
star earthed is what is meant I think Andrew
In my opinion equipment should be designed on the assumption that the mains is noisy rubbish of uncertain voltage. It should take steps to deal with it and make sure it works properly anyway. However, we have to live with things as they are, not things as we would like them to be. Probably the worst offenders for not dealing with poor mains are power amps. Most other things should be a lot more immune to noise on the mains.
BTW, what's a star wired mains block?
One in which each outlet socket is wired in a radial fashion to the incoming cable, rather than 'daisy chained' as is more usual with distribution strips.
I don't think it makes the slighest difference, but it could be argued that star wiring allows each socket to see the same source impedance.
RothwellAudio
02-05-2017, 11:53
I don't think it makes the slighest difference...
No, me neither - the wire lengths and loop areas would be so small as to be insignificant anyway.
Dynamics
05-05-2017, 14:33
That's what this music works lite devices I borrowed was like, and it didn't offer any improvement.
https://www.google.co.uk/imgres?imgurl=http%3A%2F%2Fwww.analogueseduction.n et%2Fuser%2Fproducts%2FReflex.block1.jpg&imgrefurl=http%3A%2F%2Fwww.analogueseduction.net%2 Fmains-blocks%2Fmusicworks-reflex.html&docid=cjAGAlCnOnQf4M&tbnid=g3PNXqTh_kMVjM%3A&vet=10ahUKEwiR15_8-9jTAhWELMAKHYu7A2kQMwgdKAAwAA..i&w=362&h=254&hl=en-gb&client=safari&bih=905&biw=768&q=music%20works%20lite&ved=0ahUKEwiR15_8-9jTAhWELMAKHYu7A2kQMwgdKAAwAA&iact=mrc&uact=8
It looks like someone saw me coming with a £500 price for no difference to a normal £5.99 block from Jewson.
anthonyTD
05-05-2017, 15:04
Hi All,
please see the link below, they are now being built, and produced by Mark Grant, they have been in use now for many years, I used to build them myself, but Mark has now taken over the production of them.
Hope this helps.
Anthony,TD...
http://tubedistinctions.co.uk/mains-filters/
One in which each outlet socket is wired in a radial fashion to the incoming cable, rather than 'daisy chained' as is more usual with distribution strips.
I don't think it makes the slighest difference, but it could be argued that star wiring allows each socket to see the same source impedance.
Sorry, Barry, but I have to disagree, as years of experience in experimenting with these things has shown me differently. Don't get me wrong, the sonic improvement gained with star-earthing isn't huge, but it's significant enough to be heard, as indeed is every time lowering mains impedance (via any means) has been achieved.
Experience has shown me that the ideal mains distribution block (should one be needed) is:
a) Non-filtered with no neon lights.
b) Uses high-quality single un-switched sockets and a non-ferrous casing.
c) Star-earthed, using a good quality wiring loom.
d) Has a hard-wired, high-quality mains flex and plug.
Anyone who can't hear the difference between one of the above and your average mass-produced shite, from B&Q, is deaf! ;)
Marco.
Sorry, but I have to disagree, as years of experience in experimenting with these things has shown me differently. Don't get me wrong, the improvement with star-earthing isn't huge, but it's significant enough to be heard, as indeed is any time lowering mains impedance (via any means) has been achieved.
Experience has shown me that the ideal mains distribution block (should one be needed) is:
a) Non-filtered, with no neon lights.
b) Uses high-quality single un-switched sockets and a non-ferrous casing.
c) Star-earthed, using a good quality wiring loom.
d) Uses a hard-wired, high-quality mains flex and plug.
Anyone who can't hear the difference between one of the above and your average mass-produced shite, from B&Q, is deaf! :)
Marco.
What you say sonny?:wheniwasaboy::wheniwasaboy::yesbruv:
Dynamics
05-05-2017, 16:29
I think it's all system and mains dependent as to whether you can hear a difference in one of these star earthed blocks so I don't think it's as simple as saying if you can't hear a difference you must be deaf.
I should have, in theory and considering the price, heard a difference with the music works mains lite block at £500 (using their power lead at £300 ish) but the combined £800 difference was the same to my ears as a £35 Tacima block. About £15k worth of newish speakers, amps and cables was being used, just to say so you can take a view.
But at the Bristol show as I think I might have said, I did the isotek test. Sure many others have too! Speakers were Larsen speakers like the neat iota alphas in design. Amps were an exposure intergrated and exposure CD player. In total about £6k worth I think. Using the Ikea block, then going to the isotek Polaris, then the Aquarius and up to their latest most expensive offering, the changes were very marked. The Aquarius versus the Ikea sounded like a different amp. More dynamics, detail, and speed of attack. You'd expect this in a noisy environment but when you've got sensitive hi fi at home, I suspect it still makes a very good difference.
I reckon this is where the wise money is, if you want an upgrade on using power devices. All these power blocks that are just elaborate powerbars with nothing but a bit of copper in them maybe wired in a different way, and expensive for what they are, are a bit of a con on my experience - but I always accept others have different views. But I've consistently seen people saying they get more from power conditioning and mains regeneration than elaborate non filtered power blocks. You just need the right conditioned ones and decent devices which are sometimes expensive.
I'm trying a isol-8 minisub axis next week at home from paul at hi fi lounge, and will feed back results. It's expensive but it could take my system up a notch. It has common mode and differential rejection and dc filtering. The isotek Aquarius doesn't have dc filtering I don't think.
I'd hazard a guess devices like these will do a lot for most decent systems.
I should have, in theory and considering the price, heard a difference with the music works mains lite block at £500 (using their power lead at £300 ish) but the combined £800 difference was the same to my ears as a £35 Tacima block.
I should point out that what I outlined earlier shouldn't cost anything like £800! :eek:
Marco.
Sorry, Barry, but I have to disagree, as years of experience in experimenting with these things has shown me differently. Don't get me wrong, the sonic improvement gained with star-earthing isn't huge, but it's significant enough to be heard, as indeed is every time lowering mains impedance (via any means) has been achieved.
Experience has shown me that the ideal mains distribution block (should one be needed) is:
a) Non-filtered with no neon lights.
b) Uses high-quality single un-switched sockets and a non-ferrous casing.
c) Star-earthed, using a good quality wiring loom.
d) Uses a hard-wired, high-quality mains flex and plug.
Anyone who can't hear the difference between one of the above and your average mass-produced shite, from B&Q, is deaf! ;)
Marco.
So what about the Mark Grant (or was it made by Anthony?) mains filter unit you use?
Yup, that's used separately, for eliminating digital switching noise, which my CDP and DAC are plugged into. Very effective indeed, and I wouldn't be without it! :cool:
Marco.
Interesting varied reports.
A lot of work to be done to prove and get a handle on what is going on, and I suspect from my own expectations after doing improvement work on mains DBT to eliminate placebophile effect.
One of my power amps uses a switched-mode power supply. My room has a dedicated audio ring and some sockets wired to the main house ring (the one for that floor of the house) and I can't hear any difference with it when moved between the two rings.
Yorkshireman
06-05-2017, 10:07
I use an Isotek Minisub GII for the CDP & DAC. The power amps are direct into the ring, when putting those on the isotek.
Makes quite a difference, to the sound (better seperation, detail), cleans the noise up well, when going back to direct into the ring, the sound is more muddy for a better word.
One of my power amps uses a switched-mode power supply. My room has a dedicated audio ring and some sockets wired to the main house ring (the one for that floor of the house) and I can't hear any difference with it when moved between the two rings.
Excellent. It's always handy when you can't hear any difference, as it saves spending money or worrying about it! :)
Marco.
The Black Adder
08-05-2017, 08:43
+1 for the Mark Grant / Tube Distinctions digital filter... it's a stonkingly good bit of kit.
montesquieu
08-05-2017, 18:55
I'm with Justin on this. Been round the houses with a whole load of different mains filters, mainly when I lived over the fence from an industrial estate and the mains was noisy as hell.
Assorted filters all helped a bit but a PowerInspired 1500 was the thing that did the trick - massive improvement and a fraction of the cost of the equivalent PS Audio regenerator.
I sold it when I moved here, as the power is pretty clean and I could hear no improvement with it plugged in. (Likewise the Tube Distinctions did nothing at all here).
My biggest takeaway from all that is that problems are 100% local and you may or not hear any difference with any mains product depending on local conditions (including your kit).
The Black Adder
08-05-2017, 19:04
Someone touched on this before but doesn't a balancing transformer do the same thing?
blackstar
08-05-2017, 19:11
Yeah, the BMU has quite a following. There are a few manufacturers and they seem very reasonable on price compared to some of these mains conditioners.
Excellent. It's always handy when you can't hear any difference, as it saves spending money or worrying about it! :)
Marco.
Yes - I didn't describe my point very well as I was rather time pressured. What I meant is that the system sounded the same whether the SM power amp was wired into the dedicated ring the rest of the gear used or plugged into the normal house ring. Of course this doesn't particularly prove anything. The particular amp I'm referring to is intended to be used in the pro arena and likely with a whole bank of identical units (one for each pair of drive units); it will certainly be complying with all the relevant international RFI standards. Finally, as Marco implies, although I did compare I didn't really go searching for issues and was quite happy to let this particular sleeping dog lie after a relatively cursory investigation :).
theabbot
08-05-2017, 21:08
Is there anyway of testing your mains to see if you have a noise problem before buying anything?
Thanks
is there
Look at the waveform on a scope.
Light Dependant Resistor
08-05-2017, 23:28
Look at the waveform on a scope.
Hope you inferred reading low voltage secondary voltages, as scopes are way too sensitive to use
on mains primary readings. Low voltage secondaries to approx 20v AC can be read
but not much more. Using a conventional scope has limitations with voltage.
Cheers / Chris
blackstar
09-05-2017, 05:25
You can use a 10:1 probe and adjust the settings to suit. I've read mains on an oscilloscope many times in the past.
anthonyTD
09-05-2017, 07:41
Correct!
However, when you attenuate the voltage, you also attenuate the noise, making it harder to detect!
You can use a 10:1 probe and adjust the settings to suit. I've read mains on an oscilloscope many times in the past.
Yes - I didn't describe my point very well as I was rather time pressured. What I meant is that the system sounded the same whether the SM power amp was wired into the dedicated ring the rest of the gear used or plugged into the normal house ring. Of course this doesn't particularly prove anything. The particular amp I'm referring to is intended to be used in the pro arena and likely with a whole bank of identical units (one for each pair of drive units); it will certainly be complying with all the relevant international RFI standards. Finally, as Marco implies, although I did compare I didn't really go searching for issues and was quite happy to let this particular sleeping dog lie after a relatively cursory investigation.
Yup... All you can do with these things is 'suck it and see', as you'll never achieve the same results in every system, or property where tests are tried, simply because both mains quality itself and sensitivity of the equipment to it varies, thus what happens in the final analysis is dependent on a number of factors.
However, experience tells me that when noise/interference are effectively addressed by the judicious use of filters, mains regenerators, separate spurs, etc, particularly when as a result mains impedance is reduced to a notable degree, the effect of that is *always* very clearly audible :)
Incidentally, one of the most effective ways I've found of reducing noise on the mains, which usurps that of anything discussed here, and which is rarely mentioned, is installing a dedicated earth solely for your hi-fi system, via the use of multiple copper rods [plunged into a damp area of your garden], which is tagged onto a separate mains spur (with consumer unit).
The installation of said dedicated earth almost completely isolates your system from noise/interference present on the standard house ring-main and earth, in a way that simply isn't possible with a separate spur alone, and subsequently allows your system to perform to its maximum capability. In my view, if it's practical to achieve in the property where you live, this should be done before the purchase of any expensive active mains treatments, as it could negate any need for their use at all.
Marco.
Light Dependant Resistor
09-05-2017, 07:59
You can use a 10:1 probe and adjust the settings to suit. I've read mains on an oscilloscope many times in the past.
NO this is not to be done,
1. Because the oscilloscope ground probe is at safety earth potential - inviting active mains
to be shorted, or neutral to be shorted to safety earth !.
To qualify this a bit more https://www.youtube.com/watch?v=SUVpRVI06cc move cursor to 8.03
2. Scope Probes are not designed for high voltages, although they appear insulated they do not meet
insulation criteria for high voltage measurements.
To do such a measurement you would traditionally use a isolation transformer at much lower potential
so always viewing from the secondary side of that transformer to see the primary waveform.
Or use an industry approved isolation device designed for such measurement to then interface
with an oscilloscope,
Cheers / Chris
anthonyTD
09-05-2017, 08:12
Chris,
With all due respect, I am pretty sure that the safety aspect was not at question here, Milo [Blackstar] was merely explaining that the mains can be read on a scope, using attenuation!
NO this is not to be done,
1. Because the oscilloscope ground probe is at safety earth potential - inviting active mains
to be shorted, or neutral to be shorted to safety earth !.
To qualify this a bit more https://www.youtube.com/watch?v=SUVpRVI06cc move cursor to 8.03
2. Scope Probes are not designed for high voltages, although they appear insulated they do not meet
insulation criteria for high voltage measurements.
To do such a measurement you would traditionally use a isolation transformer at much lower potential
so always viewing from the secondary side of that transformer to see the primary waveform.
Or use an industry approved isolation device designed for such measurement to then interface
with an oscilloscope,
Cheers / Chris
blackstar
09-05-2017, 08:17
Battery powered scopes are ideal for this, but I disagree about the probes not being up to it. I have had to probe mains on many occasions in the past, and I used an old battleship of a scope and its probe (I think it was called Powerscope - its been that long); I assure you that it was designed to scope big voltages.
With regard to attenuation of noise with a 10:1 probe, you just need to examine the waveform more carefully. I will say that I was never examining waveforms for the noise they were carrying in the past, so my experience may vary from yours.
Light Dependant Resistor
09-05-2017, 08:28
Hi Anthony
No it cannot be done safely without an isolation device because of the design of scopes
BNC which is wired to safety earth, this then extends out to the probe flying lead
Scope probes have the probe ground at safety earth potential. Grab a multimeter
and confirm close to zero ohms.
Now picture the scope ground lead connecting to active mains - you then get the
scope probe ground diverting active straight to safety earth.
So always measure using a isolation transformer or approved device
to interface with a scope.
RothwellAudio
09-05-2017, 08:46
No it cannot be done safely without an isolation device because of the design of scopes
BNC which is wired to safety earth, this then extends out to the probe flying lead
Scope probes have the probe ground at safety earth potential. Grab a multimeter
and confirm close to zero ohms.
My scope's input can be grounded or floating. I thought that was normal for most scopes.
anthonyTD
09-05-2017, 08:47
Measuring mains voltage with any form of test equipment is risky at best, again, the safety aspect here was not in question!
A...
blackstar
09-05-2017, 09:06
Measuring mains voltage with any form of test equipment is risky at best, again, the safety aspect here was not in question!
A...
...and no-one 'chooses' to take a mains whack, do they?!
RothwellAudio
09-05-2017, 09:10
True, the OP's question wasn't about safety but idea of actually testing the quality of the mains makes sense to me.
Incidentally, one of the most effective ways I've found of reducing noise on the mains, which usurps that of anything discussed here, and which is rarely mentioned, is installing a dedicated earth solely for your hi-fi system, via the use of multiple copper rods [plunged into a damp area of your garden], which is tagged onto a separate mains spur (with consumer unit).
The installation of said dedicated earth almost completely isolates your system from noise/interference present on the standard house ring-main and earth, in a way that simply isn't possible with a separate spur alone, and subsequently allows your system to perform to its maximum capability. In my view, if it's practical to achieve in the property where you live, this should be done before the purchase of any expensive active mains treatments, as it could negate any need for their use at all.
Marco.
I used to have just such an additional earth at my previous home (as well as a dedicated ring) and did think it was of benefit. Mine was as well as the normal ring main earth and I presume that is what you mean Marco - you aren't suggesting disconnection of any earth bonding?
The music room in my current house is two floors up and the difficulty of routing the wire has so far discouraged me from repeating the earth idea - though I may still do it. However, the wiring in my house was relatively recently replaced and is very low impedance with very thorough earth bonding throughout.
Light Dependant Resistor
09-05-2017, 09:41
True, the OP's question wasn't about safety but idea of actually testing the quality of the mains makes sense to me.
Yes can be done safely by using a low voltage transformer secondary like 12VAC then interfacing with a scope , in effect you are then looking back at the mains quality.
via the secondary voltage.... such is the nature of AC. Lorentz theorem applies https://en.wikipedia.org/wiki/Reciprocity_(electromagnetism)
Cheers / Chris
I used to have just such an additional earth at my previous home (as well as a dedicated ring) and did think it was of benefit. Mine was as well as the normal ring main earth and I presume that is what you mean Marco - you aren't suggesting disconnection of any earth bonding?
Nope, most certainly not, as that could potentially be lethal! Simply that, having a dedicated earth for your hi-fi, which is separate from the ring-main earth, is a sonically beneficial thing to do :)
Marco.
RothwellAudio
09-05-2017, 10:01
Yes can be done safely by using a low voltage transformer secondary like 12VAC then interfacing with a scope , in effect you are then looking back at the mains quality.
via the secondary voltage.... such is the nature of AC. Lorentz theorem applies https://en.wikipedia.org/wiki/Reciprocity_(electromagnetism)
But you aren't scoping the mains if you do that - you're scoping the output of the transformer, and that isn't the same thing at all.
Light Dependant Resistor
09-05-2017, 10:41
But you aren't scoping the mains if you do that - you're scoping the output of the transformer, and that isn't the same thing at all.
No, if nothing else is attached downstream, due to reciprocity you are looking back at the mains via the electromagnetism properties of transformers.
Hence the transformer is coupling at a lower potential exactly what the mains is doing.
Think of disturbances from fridge motors etc these can be seen as momentarily upsetting the mains, and reflect almost instantaneously
as noise. Attach an electric drill to a mains socket, you will see all sorts of jagged waveforms when the drill runs. The same waveforms
will be seen on the safe secondary side of a transformer viewed with a scope, as exist originating on the primary side.
You are viewing alternating current originating from the mains because there is no other source. If viewed in a DC sense there is direction ie work transferring back
via the secondary neutral ie a load etc and therefore dissipation and difference of the original activity , but this is just AC measurement, hence because it is cyclic
it is a true reflection up to the coupling properties of the transformer - in this case at a lower and safe potential capable of being read by a scope. Thinking too
that the transformer is a low impedance and the scope a high impedance - the scope is not going to contribute to any error or possibility of loading the transformer down
rather it just faithfully reads alternating current from the mains source.
RothwellAudio
09-05-2017, 11:11
Thanks for the lesson in what a transformer is.
If I want to look directly at the mains with a scope, I will. I'll accept responsibility for my own actions if I blow myself up.
Nope, most certainly not, as that could potentially be lethal! Simply that, having a dedicated earth for your hi-fi, which is separate from the ring-main earth, is a sonically beneficial thing to do :)
Marco.
If you mean "in addition to", then so be it (though depending on the earthing arrangement provided by the supplier there might be safety issues). If you mean that your audio system is only earthed via this separate dedicated earth, then that could be dangerous under, albeit rare, fault conditions outside of your property.
When I was an apprentice with the Min of Tech., about 18 or 19, we all used a Tectronics scope with an I/P max of 1000v to look at the mains. There was never a problem, but things were much 'looser' then, one of us being 'flung' across the lab because his forearm touched a colour TV HT.
I appreciate the improved safety of using a transformer, but it will alter what is seen, particularly the HF end, and it will effectively 'profile' the FR.
Oh, and a last thought, my mains, which still has a certain '60s configuration and is still legal, has the mains -ve shorted to the mains earth with a chunky bit of metal.
I bet there are scopes specifically designed for HV.
anthonyTD
09-05-2017, 16:39
Hi Dennis,
I have always used a scope to look at the incoming mains condition, and I totaly agree; using a transformer to isolate the mains is; as you say defeating the object, as the transformer will more than likely filter out any noise that was present on its primary' by the time it comes out of the secondary side. As I stated at least twice now, any measurements taken at the full mains potential, is always a high risk, no matter what type of equipment your using!
And yes, in theory, the neutral should be at the same potential as the earth, however, due to cable lengths, the distance between ones property, and the sub transformers, and ofcourse, the earthing arrangment itself; there is always some voltage potential between neutral and earth, which may be a fraction of a volt, or up to a couple of volts.
At the moment, mine measures around .8v [thats 800mv] between neutral, and earth.
A...
When I was an apprentice with the Min of Tech., about 18 or 19, we all used a Tectronics scope with an I/P max of 1000v to look at the mains. There was never a problem, but things were much 'looser' then, one of us being 'flung' across the lab because his forearm touched a colour TV HT.
I appreciate the improved safety of using a transformer, but it will alter what is seen, particularly the HF end, and it will effectively 'profile' the FR.
Oh, and a last thought, my mains, which still has a certain '60s configuration and is still legal, has the mains -ve shorted to the mains earth with a chunky bit of metal.
I bet there are scopes specifically designed for HV.
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