Balanced Mains - first impressions very favourable

[worrasf]

First off my sincere thanks to Mark (Reid Malenfant) for his invaluable help earlier today :respect:

So I've installed a balanced mains supply (BMS) in my dedicated mains supply I bought this one (http://www.airlinktransformers.com/transformer/bp3120-bp3120-balanced-power-supply.asp) with screw terminals as I wanted to put it in the loft where there was (relatively) easy access to the mains cables and any transformer noise would be inaudible. As the power was off I took the opportunity to clean all relevant contacts both mains and interconnects with Deoxit.

To be honest I didn't really know what to expect there was a bit of "it just seemed a good idea" but I have immediately noticed a huge improvement.

There is a big increase in dynamic range - particularly noticeable in lower bass extension but also definitely audible in the high frequency range. Within this extended range the dynamics (PRaT) are significantly improved (faster & sharper).

Stereo imagery and focus is tighter - I didn't notice any difference in the 3D presentation - instruments and voices were not pushed forward or back - they just seemed to be placed more solidly in space. The inter-track silence on CD is "black" as it seems the noise floor has dropped. It is as if the system is somehow now less constrained and not working as hard.

The effect was noticeable on both CD and vinyl but the most dramatic improvement was with vinyl. I think there is a little less hum from the amps but it's not a huge improvement in this area.

So a "night and day" difference and thats in a system plugged into a dedicated mains not on the "mucky" domestic ring main.

The unit I chose wasn't a straight forward "plug and play" (although the manufacturer makes these also where you just plug the mains lead into your wall socket) and I ended up having to disconnect and remove the mains earth wire from the back of the wall socket to get the mains to balance (thanks Mark) so it took a few hours to get it right but I am very pleased with the result.

It's a big lump and weighs in at 18Kg and is butt ugly :booty: but at the price (£304.80 inc VAT and delivery) IMHO is a very cost effective way of significantly improving system performance.
:cool:


Steve

[Reid Malenfant]

Glad to have helped Steve, but there is a way of doing it cheaper :eyebrows: If you had got in touch first i reckon you could have had a 4.4KVA continuous (6.6KVA for 30 minutes) setup with just a little work for about £100 delivered ;) Maybe a few bits on top that would have added maybe £20 at the most.

It's early days, but i reckon you'll soon notice that there are other differences. Balanced mains due to it's nature cancels out certain forms of distortion that can afflict the supply. You have already noticed an improvement in the lowering of the noise floor which i would expect...

Lets see what you reckon in a month as i have a feeling you'll find other benefits :)

ATB chap :cool:

[worrasf]

If you had got in touch first i reckon you could have had a 4.4KVA continuous (6.6KVA for 30 minutes) setup with just a little work for about £100 delivered ;) Maybe a few bits on top that would have added maybe £20 at the most.


Aaagh :unfair:

Steve

[Reid Malenfant]

Indeed, but if you had searched this forum you'd have seen me purchasing two 3.3KVA 'site transformers' that are used to convert 240V to 120V balanced about an earth... A little modification made them do 240V balanced between the pair of them :doh:

[Glen B]

To be honest I didn't really know what to expect there was a bit of "it just seemed a good idea" but I have immediately noticed a huge improvement.

There is a big increase in dynamic range - particularly noticeable in lower bass extension but also definitely audible in the high frequency range. Within this extended range the dynamics (PRaT) are significantly improved (faster & sharper).

Stereo imagery and focus is tighter - I didn't notice any difference in the 3D presentation - instruments and voices were not pushed forward or back - they just seemed to be placed more solidly in space. The inter-track silence on CD is "black" as it seems the noise floor has dropped. It is as if the system is somehow now less constrained and not working as hard.

I have been using balanced power for the past 7 years. Your experience mirrors mine almost 100 percent.

[Tarzan]

Err, what is balanced power?

[Glen B]

Balanced power is a form of "power conditioning" that employs balanced isolation transformers to reduce AC mains common-mode noise. The majority of users report benefits similar to those described above. See the following links, which explain all about balanced power.

http://www.equitech.com/articles/bpng.html

http://www.equitech.com/articles/overview.html

http://www.equitech.com/articles/origin.html

[Reid Malenfant]

Only difference is in the UK it'd be 120V AC on each live line rather than 60V AC :)

Nice find Glen, saved me a load of typing :eyebrows:

[Tarzan]

Thanks chaps, sounds interesting:).

[worrasf]

I have been using balanced power for the past 7 years. Your experience mirrors mine almost 100 percent.

Always good to have independent confirmation of my findings :)

I am staggered by how much improvement the balanced mains has brought to the sound of my system. I find myself wondering why this remains a little known "secret tweak" and not on the main stream audio upgrade path :scratch:

Steve

[Reid Malenfant]

Big transformers can cost a heck of a lot of money :rolleyes: You really need to overate the things quite a bit to avoid too much transformer regulation, IE voltage drop.

I agree though, balanced mains is superb. Can't wait to get my whole system running balanced :eyebrows:

[worrasf]

Big transformers can cost a heck of a lot of money :rolleyes:
True - but mine cost just over 300 squids (price of a mid ranking cartridge) and you could make even cheaper. Admittedly, a certain dealer not a million miles from Donald Campbell requires you take out a mortgage for a transformer and bits but those units from Airlink seem pretty cost effective.

Steve

[Reid Malenfant]

Agreed Steve, as i mentioned with a bit of messing about it'd be possible to make a 4.4KVA continuous balanced mans setup for about £120. Well that's assuming i could find the relevant transformers again :eyebrows:

So as tweaks go it can be very worthwhile, if you know what you're doing ;)

[worrasf]

So as tweaks go it can be very worthwhile, if you know what you're doing ;)

Touche Mark :fence:

But if one went for the "plug straight into the wall socket" unit rather than trying to be a smart :booty: with the "wire it direct into the mains ring" unit like someone not a million miles from here it would be much simpler.
:hmm:

Steve

[MCRU]

Always good to have independent confirmation of my findings :)

I am staggered by how much improvement the balanced mains has brought to the sound of my system. I find myself wondering why this remains a little known "secret tweak" and not on the main stream audio upgrade path :scratch:

Steve

because you could end up dead if you don't know what you are doing

[worrasf]

because you could end up dead if you don't know what you are doing

Mmm! Not sure how much knowledge is required to plug this into an existing wall socket - http://www.airlinktransformers.com/transformer/bps2000-balanced-power-supply.asp


Steve

[MCRU]

Mmm! Not sure how much knowledge is required to plug this into an existing wall socket - http://www.airlinktransformers.com/transformer/bps2000-balanced-power-supply.asp


Steve

hello mate
its not little known as they sell loads, however people like to experiment with mains and the point I was making is if you are reading this and similar threads DON'T mess with electricity unless you know what you are doing, get a lekky in. That was all I was saying.

[worrasf]

DON'T mess with electricity unless you know what you are doing

Totally agree with that comment David.

Steve

[Glen B]

Always good to have independent confirmation of my findings :)

I am staggered by how much improvement the balanced mains has brought to the sound of my system. I find myself wondering why this remains a little known "secret tweak" and not on the main stream audio upgrade path :scratch:

Steve

I think a lot of people are just sceptical of such tweaks, no matter how much others claim to hear improvements. That said, there are a number of North American manufacturers of factory-built balanced power units, including Balanced Power Technologies (BPS), Furman Sound, Torus Power, Equi=Tech, Blue Circle Audio, AlphaCore, and Transcendent Sound.

http://www.toruspower.com/category/products/

http://www.equitech.com/products/rack/modelqav.html

http://www.transcendentsound.com/Transcendent/Transcendent_Sound_Power_Supply.html

http://www.bluecircle.com/index.php?menu_id=2724

http://www.b-p-t.com/balanced-power-ultra-isolators.html

http://www.furmansound.com/product.php?div=02&id=IT-REF_20i

[jantheman]

Do you have a DVM Steve...I would be interested to see the difference in voltage between the inpuit and output......

[worrasf]

Do you have a DVM Steve...I would be interested to see the difference in voltage between the inpuit and output......

Hi Ray,
I do have a DVM but I installed the BMS using an analogue VM. I did not detect any difference between the input voltage from the mains going into the transformer and the output voltage at the wall sockets measured live - neutral, live- earth (50%) and neutral - earth (50%). The BMS transformer is in the loft - next time I have cause to go up I'll put a DVM across the input terminals and then at the wall sockets and let you know but going by the AVM readings if there is a difference it will be negligible.

Steve

[Ali Tait]

It will drop a little depending on the load.

[jantheman]

It will drop a little depending on the load.

The opposite is true in my case...V/OUT is 4.7% higher than V/IN.....measured with no load.

[Glen B]

With balanced power, difference between input and output tells you nothing. At no load, the voltage at the secondary will always be slightly higher than the primary. Exactly how much will vary some from one transformer to the next.

What matters with balanced power is that the voltage between the center tap and ends of the secondary winding be as identical as possible. This is achieved by the transformer manufacturer getting the center tap as close as possible to the center of the secondary winding. The smaller the difference in voltage between the two halves, the better the common-mode noise rejection value, and vice versa.

[jantheman]

Accumulation of tolerances.............

[Ali Tait]

The opposite is true in my case...V/OUT is 4.7% higher than V/IN.....measured with no load.

Aye, but put some load on it and watch V/out be less than with no load.

[jantheman]

Aye, but put some load on it and watch V/out be less than with no load.

I agree...but....look at it from this point of view......
Measuring the O/P of the balanced transformer........
With no load I get a reading of 259V...outside the accepted tolerance for mains in the UK. The spec for UK voltage is now 230V +10v -6v. Fudged to harmonise with the rest of Europe. Just a note..my mains tends to run quite high, as I write its at 247V.
Looking at this then the max 'in tolerance' voltage should be 253V. So..I'm +6V on this.
For every 100W I plug in I get *about* a 1V reduction in the voltage out.
So, I'm going to have to have a *constant* power draw of some 5/600W in order just to stay within the current accepted tolerance.
There are 1 or 2 items of my hifi gear that I dont switch off but they dont even add up to 100W so they would be running well outside of the tolerance limit for UK voltage.
Is this voltage damaging to said kit, no one will say, least of all the designers...........

[Reid Malenfant]

What's the VA rating of the balanced transformer Ray?

I have a cunning plan :eyebrows:

[jantheman]

What's the VA rating of the balanced transformer Ray?

I have a cunning plan :eyebrows:
1500VA....and dont say a Variac..cos I already have one........:lolsign:

[Reid Malenfant]

1500VA....and dont say a Variac..cos I already have one........:lolsign:
No, you just need a 50VA 6V transformer me old fruit! :lol:

I made this diagram to show how i think the VPhase unit works, in your case you'd need a 50VA 6V transformer to step the mains voltage down slightly for safetys sake ;)

4616

[jantheman]

No, you just need a 50VA 6V transformer me old fruit! :lol:

I made this diagram to show how i think the VPhase unit works, in your case you'd need a 50VA 6V transformer to step the mains voltage down slightly for safetys sake ;)

4616

Transformer Bucking.........thought about it...and....still thinking about it...:lolsign:
EDIT....But why only 50VA???

[Reid Malenfant]

The thing is it'd work! :)

[jantheman]

Dont think you saw the edit to my last post....
Why only 50VA....???

[Reid Malenfant]

With a 1500VA balanced transformer the primary current will be about 6 Amps or just a tad more at full load. As you only need to drop the voltage by 5 or 6V & you only need a secondary capable of carrying just over 6 Amps (the primary current of the balanced transformer) you don't need anything bigger than 50VA ;)

Here's your prize (http://cgi.ebay.co.uk/High-Quality-50VA-Toroidal-Transformer-0-6-0-6-Va-/270752825825?pt=UK_AudioElectronicsVideo_Video_Tel evisionSetTopBoxes&hash=item3f0a2041e1) :cool:

Another interesting thing about doing this is you'll get better regulation than just the balanced transformer on it's own :) As the load increases the output of the balanced transformer will decrease voltage wise. The same will happen to the output of the buck transformer as the load increases, which will have the effect of slightly increasing the mains voltage to the balanced transformer :lolsign:

[worrasf]

Do you have a DVM Steve...I would be interested to see the difference in voltage between the inpuit and output......
Hi Ray

OK so have got the DVM out and guess what? no difference between input and output and no difference under load or not.

I get a steady 245V regardless of whether kit is all off or all on (thats 4 PSU's, power amp, preamp, CD transport, headphone amp. I get a steady 122v across each leg regardless of load.

Measuring input (taken from adjacent socket on non-balanced mains) I get a steady 245v.



Steve

[Reid Malenfant]

I doubt you'd ever draw more than about an eighth of the KVA capacity of that transformer though Steve. It's big enough to have good regulation so i doubt you'd see any :eyebrows:

[worrasf]

I doubt you'd ever draw more than about an eighth of the KVA capacity of that transformer though Steve. It's big enough to have good regulation so i doubt you'd see any :eyebrows:

So do you think it was a "good buy" Mark given what I am using it for?

Steve

[Reid Malenfant]

Yes. You have a really nice low impedance supply which as a bonus is balanced :) Always best to use oversized transformers & seeing that is now the most important in your system imo it was a wise choice!

Besides which you only need to listen to your present system & make your own mind up.

[jantheman]

Nice one Steve...looks like going OTT in power spec is the way to go.
Thanks for your help Mark...I may give it a go, just for fun, but go for 12V 100VA or similar. Like I said previously I'm using a Sercal plugin and am very happy with that.

[electric beach]

Mmm! Not sure how much knowledge is required to plug this into an existing wall socket - http://www.airlinktransformers.com/transformer/bps2000-balanced-power-supply.asp


Steve

Many thanks for your investigation, linky and posting Steve. This will make me get the balanced power thing done, when previously I thought it was going to take about a grand. Even I can plug in a plug :eek: (although I did get shocked once when about 12 years old; trying to use a socket behind the bed and put my finger on the earth pin to locate the holes :doh:)

[Reid Malenfant]

You sure as hell didn't touch just the Earth pin Steve, only Live will give you a shock & then you need a connection to either Earth or Neutral as well...

Guess i'm used to the feeling of ball bearings shooting up my arms :eyebrows:

[jantheman]

Mark..just for your info.
I picked up one of these on Fleabay. Brand new and 12V 160VA rating. Cost me a tenner +post.
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=361-7998&x=0&y=0
Wired in OK, slightly differently to how you suggested but works fine.
http://sound.westhost.com/articles/buck-xfmr.htm
See Fig 4.

[Reid Malenfant]

First link doesn't work Ray, but that hardly matters :eyebrows: The second one is much more interesting, cheers for the link ;)

Glad it's working for you fella :cool:

[jantheman]

Link updated Mark...try again.

[Reid Malenfant]

Yep, that'll do the job :) I guess you paralleled the secondaries ;)

[jantheman]

Yep, that'll do the job :) I guess you paralleled the secondaries ;)

Havent yet but I dont suppose it will hurt. Been scanning t'internet for a suitable box but no luck yet.....I need something with internal measurements about 5" (125mm) cube. That would be a good size.

[Reid Malenfant]

It might hurt not to parallel them if you ever happen to get near the 1.5KVA rating of the balanced transformer. Besides which you'll get better regulation & have a slight overload factor as per that artical. Right now assuming you haven't put the two secondaries in parallel you'd have a reduced total power rating ;)

[jantheman]

Now in parallel. Easy just spring clips. Now...wheres the box............

[Reid Malenfant]

So how are you getting on with it Ray & how's it sounding now you have a balanced supply?

Are you running your power amp or integrated from it?

I'm interested chap that's all. I have all my front end powered via the balanced output of a PS Audio P600, but the power amps are connected to regular unbalanced mains ;) The P600 would go into meltdown attempting to supply the power amps :eyebrows:

E2A:- i'll keep my eyes open for a suitable enclosure for you, bit of an odd size though isn't it :)

[jantheman]

Well its in a box and all seems to be working fine. Havent attached it to my system yet as I'm planing a small reorganisation so I am waiting to do that just to get decent access to the back of the rack. Will let you know how it goes.
http://i1120.photobucket.com/albums/l499/jantheman87//HiFi/DSCN0185.jpg

[Volante]

This post is interesting.

So is there a balanced power unit available which a complete non-tekky like me could safely use to provide power to my system without degrading the sound and dynamics etc? Are the units or their benefits system dependent? I sometimes (in winter temperatures) use a Viva Solista 845 integrated or otherwise various pre's and a Croft Twinstar 4/5 power amp. Currently (no pun intended) power for my system is fed through two Vertex Taga distribution boxes daisy-chained to the 13A wall socket.

My system is sited in my study so the balanced power unit would, depending on size, be able to be sited in the corner somewhere - i.e. it's not going to be in a living room where one of these things would be completely unacceptable. Apart from being ugly and heavy do they hum or have any other anti-social habits?

I am confused as to whether I should be seeking a plug in and play version from the unnamed person "not a million miles from here" whom some people are referring to (I don't know who it is!) or something that someone would make up for me and I could plug in to the 13A wall socket?

Apologies in advance if I have got the wrong end of the stick!

Any assistance/recommendations would be welcome. Thanks

[Glen B]

Of course there are plug-and-play balanced power units. I don't know what plug-and-play brands you have available in the UK, but major players like Equi=Tech and Torus both make units for international use.

http://www.equitech.com/products/rack/modelqav.html

http://www.toruspower.com/category/products/