MGE Ultra-Isolation Noise Transformer, 5 KVA MODEL 91005-31T

ddk

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I think I will wire two of the four plugs that I have dedicated to my setup, and try just two through the transformer. Then I would have the option of trying both ways. If I like what I hear I will probably wire the others through the transformer.

I do not have any ground loops. My preamp and phono have ground lifting switches so I have those configured so I get zero hum as far as loops are concerned. I had a separate ground plate installed and ground isolating plugs wired, but I found zero benefit doing that. I may use that ground plate and have the new breaker box grounded to that. The main breaker box is grounded to a cold water pipe. I also only have a 100 AMP service. Too many large and small factories around that I assume would affect my power in my area.

The main thing I want to address is the physical hum I am getting from my amp. The power transformer hums, depending when I listen during the week it is very annoying walking into a quiet listening room and hearing that transformer humming. I know the amp was quiet at the dealers room. The builder of my amp says I have DC polluting my power, I borrowed an item from Blue Circle http://www.bluecircle.com/page129.html and it was very effective. It did what it was supposed to do, but I felt the it was a sonic compromise I was not willing to accept.

Paul

Any transformer will have a sonic penalty, you're not going to get away from that. I have to agree with with TP1, your amp designer has a responsibility here. I don't know thei brand he used but they could be low in quality or defective, it happens even with the best transformers and often manufacturers are either adamant to reject them or sometimes the defect shows up later.

david
 

TP1

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Apr 2, 2014
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Some of the problem could be blamed on the transformer, the builder is now supplying the amp with an air gapped transformer, and the case surrounding it has been more heavily damped. The hum is also amplified by the case. Problem is I cannot remove the tranny case and damp it so it doesn't ring because the bolts are covered by too much of the circuit. I would send it back but, he is on the other side of the Atlantic ocean.
When I had a pair of Lamm ML1's is hummed as well in the same room just not as loud and they had potted transformers.

I had a conversation with a tech at the Furman factory and he said one of their Symmetrical balanced power conditioners. He was quick to point out the hum may transfer to the conditioner.

"Symmetrical balanced" transformers, balanced power supplies etc are all in fact toroidal isolation transformers with a centre tapped earth. The fancier the name and the prettier the presentation - the more expensive the price, but they are all as I described. Being toroids, DC will make them vibrate but quite a few amp manufacturers use toroidal transformers and have strategies in place to keep them silent.

One option would be to hard wire a decent size transformer in a more remote location so if it did make a noise you wouldn't hear it. If you were going down that route a balanced, isolating transformer will also give the system a significant sound upgrade because it eliminates electrical noise present in the power lines. Isolation transformers do not
 

pcosta

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Jul 25, 2010
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"Symmetrical balanced" transformers, balanced power supplies etc are all in fact toroidal isolation transformers with a centre tapped earth. The fancier the name and the prettier the presentation - the more expensive the price, but they are all as I described. Being toroids, DC will make them vibrate but quite a few amp manufacturers use toroidal transformers and have strategies in place to keep them silent.

One option would be to hard wire a decent size transformer in a more remote location so if it did make a noise you wouldn't hear it. If you were going down that route a balanced, isolating transformer will also give the system a significant sound upgrade because it eliminates electrical noise present in the power lines. Isolation transformers do not

This is what I am thinking of buying http://www.pacificparts.com/vends/mge/images/t1.pdf The 5KVA 240v/120v. It would be outside my listening room. Can those be wired "balanced".
 

Nyal Mellor

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Any transformer will have a sonic penalty, you're not going to get away from that.
david

I don't think that is fair. At least with Torus I hear no sonic penalty, only benefits, as do others such as DallasJustice on this forum and Jeff Fritz of Ultra Audio (Soundstage) with highly resolving systems.
 

Nyal Mellor

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If you were going down that route a balanced, isolating transformer will also give the system a significant sound upgrade because it eliminates electrical noise present in the power lines. Isolation transformers do not
Even a balanced isolation transformer with electrostatic shields will let through some noise due to coupling. The only benefit to balancing is that it theoretically eliminates noise present on both power lines (common mode noise).

BTW the Torus balancing approach is 240V in via two 120V legs, 120V out. No center tapped ground.
 

dallasjustice

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Apr 12, 2011
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Any transformer will have a sonic penalty, you're not going to get away from that. I have to agree with with TP1, your amp designer has a responsibility here. I don't know thei brand he used but they could be low in quality or defective, it happens even with the best transformers and often manufacturers are either adamant to reject them or sometimes the defect shows up later.

david
Not with a Torus. After I had the rm60 installed, I sold all of my mega bux power cables. Power cables have NO impact on sonics if using the Torus. The rm60 ended up saving me money since I sold much more in PCs than I paid for the Torus RM60.
 

Mike Lavigne

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I am having a tough time believing that statement.

certainly top level 'whole system, sufficiently scaled, isolation transformers' such as a Torus or like my Equi=tech change how power cords and stand alone separate box power conditioners work in a system. after my Equi=tech was installed the simplest power cord worked the best; while prior I needed noise reduction even at the expense of purity.

lower whole system noise and increase dynamic contrasts and then find power cords that do the least.....and allow the most music signal to come thru.

I'm not sure that power cords don't matter with top level whole system isolation transformers, but I do think that if they have their own 'character' then they get in the way of ultimate system performance.
 

rockitman

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Sep 20, 2011
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certainly top level 'whole system, sufficiently scaled, isolation transformers' such as a Torus or like my Equi=tech change how power cords and stand alone separate box power conditioners work in a system. after my Equi=tech was installed the simplest power cord worked the best; while prior I needed noise reduction even at the expense of purity.

lower whole system noise and increase dynamic contrasts and then find power cords that do the least.....and allow the most music signal to come thru.

I'm not sure that power cords don't matter with top level whole system isolation transformers, but I do think that if they have their own 'character' then they get in the way of ultimate system performance.

That is interesting explanation to me. That said, it all depends on the power cord and system, imo. I am confident that the cords I use now sound better in my system than the 8 awg PS Audio AC-12's I used before. If the isolation trans drops the noise floor, it is logical to assume that a great cord can even be better. I am doing a subpanel off the mains in the near future. I will see how much that drops my noise floor. I run the amps direct into the wall and don't believe in power conditioning for amps. This thread has me concerned about transformers with regard to Hummmmm.
 

Occam

[Industry Expert]
Dec 15, 2010
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Even a balanced isolation transformer with electrostatic shields will let through some noise due to coupling. The only benefit to balancing is that it theoretically eliminates noise present on both power lines (common mode noise)
....

Nyal,

My understanding is that common mode attenuation is an inherent characteristic of transformers.

The specific benefit of balancing / Technical power transformers, beyond that of a conventional isolation transformer, is that leakage currents from the fed component's chassis and safety ground, from the anti-phase legs are going to be equal but anti-phase and net to zero (theoretically, the reality dependent upon the actual component being fed the balanced/technical power.)

FWIW,
Paul
 

Nyal Mellor

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Jul 14, 2010
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That is interesting explanation to me. That said, it all depends on the power cord and system, imo. I am confident that the cords I use now sound better in my system than the 8 awg PS Audio AC-12's I used before. If the isolation trans drops the noise floor, it is logical to assume that a great cord can even be better. I am doing a subpanel off the mains in the near future. I will see how much that drops my noise floor. I run the amps direct into the wall and don't believe in power conditioning for amps. This thread has me concerned about transformers with regard to Hummmmm.

You should look at one of the Torus Power Wall Mount unit in place of your planned sub panel. I don't want to make this thread about Torus products but their transformers will not add noise to a room, even a room measured at NC20. Much is dependent on the design and manufacturing of the isolation transformer. All iso transformers are not created equal, just like amps or speakers.

http://www.toruspower.com/nbt-narrow-bandwidth-technology/
 

Bruce B

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Apr 25, 2010
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You should look at one of the Torus Power Wall Mount unit in place of your planned sub panel. I don't want to make this thread about Torus products but their transformers will not add noise to a room, even a room measured at NC20. Much is dependent on the design and manufacturing of the isolation transformer. All iso transformers are not created equal, just like amps or speakers.

http://www.toruspower.com/nbt-narrow-bandwidth-technology/

I see these are half the weight of the Equi=tech units that Mike and I have (>350lbs!). Would be much easier to mount these for sure! My electricians had to go buy hydraulic jacks to lift the cabinet in place! :eek:
 

ddk

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May 18, 2013
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Nyal, Michael and Mike, you're all confirming that transformers have certain qualities. I also mentioned that I have clients who like those qualities. Personally I find some of those qualities a type of coloration hence the penalty. I heard some of those same qualities in your room Mike when I visited you last year, the equitech has a distinct signature similar to other transformers. I feel the same about audiophile power cords, for the most part they seem to be additive or subtractive in nature. You're all acknowledging the compounded affect of transformer and audiophile power cords being less than ideal.

Fact remains that the quality of electricity has a significant affect on the sound of high end system and its atrocious in so many places, unfortunately there doesn't seem to be a cure, or I haven't found one. High quality transformers do clean up ac hash but they also take away timbre and micro dynamics along with it. My best compromise for now is to use a high quality one off line, others might find the penalty acceptable for a cleaner sound.

david
 

mep

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Well this thread took a turn that I certainly didn't anticipate and that is not everyone believes in balanced transformers for cleaning up AC in listening rooms. Those that do believe in said transformers don't seem to worship at the alter of power cords anymore. We have more than a few people on this forum who have been sheep-dipped in Shunyata magic and even sleep in Shunyata pajamas, but I don't believe any of them have balanced transformers feeding their rooms. It's a paradox I tell ya!

Speaking of pajamas, I think we could market a line of audiophile pajamas all kidding aside. You could have an entire line of different type vacuum tube pajamas, manufacture brand pajamas, analog pajamas, digital pajamas, etc. Something for all audiophiles.
 

Nyal Mellor

Industry Expert
Jul 14, 2010
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Nyal, Michael and Mike, you're all confirming that transformers have certain qualities. I also mentioned that I have clients who like those qualities. Personally I find some of those qualities a type of coloration hence the penalty. I heard some of those same qualities in your room Mike when I visited you last year, the equitech has a distinct signature similar to other transformers. I feel the same about audiophile power cords, for the most part they seem to be additive or subtractive in nature. You're all acknowledging the compounded affect of transformer and audiophile power cords being less than ideal.

Fact remains that the quality of electricity has a significant affect on the sound of high end system and its atrocious in so many places, unfortunately there doesn't seem to be a cure, or I haven't found one. High quality transformers do clean up ac hash but they also take away timbre and micro dynamics along with it. My best compromise for now is to use a high quality one off line, others might find the penalty acceptable for a cleaner sound.

david

I don't hear any negatives, only positives.
 

Nyal Mellor

Industry Expert
Jul 14, 2010
590
4
330
SF Bay Area, CA, USA
I see these are half the weight of the Equi=tech units that Mike and I have (>350lbs!). Would be much easier to mount these for sure! My electricians had to go buy hydraulic jacks to lift the cabinet in place! :eek:

Mmm Torus do make some monsters..the ones badged as Ground Zero (AIO) are floorstanding beasts, some available up to 290A continuous capacity!! But their WM units are much more reasonable in weight.
 

KeithR

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Nyal, Michael and Mike, you're all confirming that transformers have certain qualities. I also mentioned that I have clients who like those qualities. Personally I find some of those qualities a type of coloration hence the penalty. I heard some of those same qualities in your room Mike when I visited you last year, the equitech has a distinct signature similar to other transformers. I feel the same about audiophile power cords, for the most part they seem to be additive or subtractive in nature. You're all acknowledging the compounded affect of transformer and audiophile power cords being less than ideal.

Fact remains that the quality of electricity has a significant affect on the sound of high end system and its atrocious in so many places, unfortunately there doesn't seem to be a cure, or I haven't found one. High quality transformers do clean up ac hash but they also take away timbre and micro dynamics along with it. My best compromise for now is to use a high quality one off line, others might find the penalty acceptable for a cleaner sound.

david

I don't understand how you can go to someone's room and just hear the electrical conditioning system. Can you explain more?
 

ddk

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May 18, 2013
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I don't understand how you can go to someone's room and just hear the electrical conditioning system. Can you explain more?

Transformers affect harmonics in a big way, you'll recognize the signature if you lived with one. Then I ask to confirm.
 

Mike Lavigne

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I don't understand how you can go to someone's room and just hear the electrical conditioning system. Can you explain more?

of course he can't understand cause and effect that way. has he lived with all transformers? of course not. he has a right to his own opinions about the subject.

for me i can switch back and forth from Equi=tech to dirty power (those outlets are right next to my Equi=tech transformer outlets) and hear for myself what is the difference. and his view is not what i hear.
 

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