Balanced AC possible without isolation transformer?

Is balanced mains possible without the sacrifice of having an isolation transformer along the line adding unwanted impedance?
This might be a stupid question and I suspect the answer is “no”, as where would you take the center tap gnd reference from?
I would someday love to have the benefits of balanced mains in my whole house but am not willing to sacrifice the stereo performance. Maybe Equitech for the house except for a low-impedance dedicated line for the hi-fi?

Having the whole house not being a radiative, receiving bundle of antennae is an exhilarating thought.

I don’t know about the output impedance but though I use regenerators in two systems I have a third headphone only system where I use the Decware Zen Line Conditioner:

It’s not cheap, and the wait time can be a few months, but I really find this giant transformer-based unit to work very well and improve, not degrade, the sound. Like with the regenerators I can hear clearly the differences between power cables and interconnects and enjoy a great tonal balance and dynamics.

I realize this is not a whole house solution. But it is a six outlet system solution I am glad I took a chance on (I bought one of the first half dozen units sold).


So am I right in that it’s up to the size/specs of the transformer how much it will contribute to a line’s impedance? Is there a point where the losses become negligible?
I was just wondering… Art Dudley from Stereophile has an isolation transformer but he has such low wattage amplifiers that it probably makes no discernible loss to his system(s)
Just popped into my head.

you might consider that Isolation Transformers come in different “sizes”

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So the bigger the isolation transformer, the less there is impedance gain?
Equitech’s transformers are apparently far too minuscule to allow for proper high-current delivery. How big a transformer do I need to not strain a P3 Regenerator driving a high-current amp, for example? Can I easily incorporate a huge transformer with an Equitech system?

Arenith, I believe there’s little real ‘sacrifice’ to a balanced isolation transformer (hereafter ‘t-mer’)… In fact, the ‘isolation’ part of that describes one very real benefit, that of isolating the NOISE on the source 120VAC line from the two 60VAC lines on the load side and also isolating the the noise generated by equipment plugged into the load side of the t-mer from the 120VAC side… Some of us think that’s such a benefit that we have isolation transformers that aren’t also balanced transformers.

And yes, surely* the higher power rating of a balanced transformer, the larger the wiring and the lower the DC resistance.

  • To the technically educated among us, PLEASE correct my statement if necessary.

Notes to forum administrator

  1. Could someone correct this software from shortening the gramatically correct DOUBLE-space after an end-of-sentence period into a single space?.
  2. If item 1 is corrected, I’ll stop using double-periods after the ends of sentences.
  3. And perhaps at the same time, can someone correct the software’s changing the second asteric of a pair into a sold dot?

Consider a hypothetical setup with a large helium-cooled superconducting isolation transformer drawing power straight from a nuclear plant’s primary mains line. From there a balanced, dedicated line is drawn using superconducting cable, helium cooled all the way, with special thermal interconnect adapters allowing to connect the superconductors to equipment. From there on all connects are rhodium and all wiring (even internal component wiring) is silver, with the best conductor geometry for given connections. Choose your speakers - how might they sound?
Is this too much…?

Yep, you linked that wonderful page to me earlier.

But whaddaya think of my idealistic, extremely expensive and ridiculously ballistic hypothetical assembly?

Hadn’t noticed 2 (Philistine, me :wink: ), but 3 I do and it bugs me. MS software usually does it too but is at least configurable not to :slight_smile:

The “two spaces after period” rule was established during the days of typesetters, when additional space was needed to show the difference between the spacing between words (which was smaller) and the spacing between sentences (which was larger).

With the dawn of computers, word processing programs not only began offering an absurd number of fonts, but each font was programmed to space characters proportionally (“l” takes up about a third of the space “w” does). In turn, most computer fonts will automatically give you enough room between sentences with one space. And, according to nearly all stylebooks, including The Associated Press Stylebook and the Chicago Manual of Style, you always use a single space after a period.

The point is, it’s not only widely accepted, it’s expected that you use only one space after a period. Sorry two-spaces, it’s time to make the switch.

Paraphrased from: - article date 2012


Whether one types two spaces or one after a period is an accurate indication of the age of the typist.

With the advent of proportional fonts, two spaces became redundant. This began with proportional font typesetting and extended to computers once they also utilized proportional fonts.

Does the Decware product have a balanced bifilar toroidal transformer? Bifilar toroidals weigh nearly twice as much as an equivalent toroidal.

From the Plitron website:

“The Balanced Power concept consists of a 1:1 isolation transformer (ie 120 VAC In/Out) with a centre tapped secondary winding. The ‘Balanced’ refers to a Bifilar wound secondary – meaning both secondary halves are wound simultaneously, turn for turn – thus each of the 60 Volt sections are mirror imaged and matched to the theoretical limit for resistance, capacitance, and inductance.”

I’m really curious whether inserting a Torus, Equi=tech, or PLiXiR product between the P20’s output duplex and (let’s say) a DAC would be beneficial, and further, not cause any harm to the P20.

I honestly don’t know, but can tell you that the transformer is large and very heavy. Here’s a picture from the product page:


If you would like to inquire you may get an answer from the designer here:

Thanks for the photo! I’ll be reaching out to ask the manufacturer. As well as to PS Audio.

I’ve done some research using the key words “balanced power”, “toroidal”, etc. but the posts on this PS Audio forum / threads seem quite fragmented, and I can’t seem to find anyone with P10/12/15/20s having plugged a balanced (bifilar) toroidal transformer into their Power Plants. I’ll keep on asking, and looking!

I have plugged my P10 into the Decware unit. I believe there was a subtle improvement doing so, but it wasn’t significant enough for me to eithe repurpose the Decware unit from my headphone system or to warrant purchasing another so that I could have one in both systems. I’m lucky here in that I live in a wooded sparsely housed area with a less noisy than urban power (usually less than 2% noise in the line) and I think if my incoming power is worse having the Decware unit in front of the P10 might make a more significant difference. In the headphone system it’s a very good nerve-center, I really enjoy having it.

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For many years I tried to get a good sound at a low cost. I couldn’t afford big expenses and as an electronics engineer I wanted to do something myself. I have assembled several amplifiers and several loudspeakers. I remember a huge improvement in the sound when I coiled the crossover coils with silver plated wire.
And now I switch to isolation transformers.
For about 20 years I used 230/230 V, 450 VA and 200 VA transformers, each of them improved the sound of the system. The transformers themselves, without additional elements, only for safety I placed them in a suitable housing. I tried the 200 VA transformer with a pair of active Neumann KH 310 monitors, they sounded great. I made a test then with the addition of a polypropylene capacitor to the secondary winding, I do not remember what capacity, but it made the sound worse.
Two years ago, after purchasing P5, DMP and DSD, I passed the transformers to my colleagues. Everyone is happy with them, I was even asked to prepare one more and then I bought another 450 VA transformer. It was supposed to be the same as before, but this one did not improve the sound. I took measurements of the old and the new transformer. The output voltages were identical, the winding resistance also. They differed in winding impedance. The transformer giving a good sound had an impedance 10 times lower, consumed 50 mA of current without load, the transformer not improving the sound consumed 10 mA.
The transformer manufacturer informed me that the cores are now buying from another manufacturer. Theoretically, a core with higher magnetic permeability is a better core, but not in this application.

What is this assessment based on? Especially in comparison to a P3’s rather modest capabilities?

Lon, there is a similar discussion going on over at WBF about whether and how to connect a regenerator with a balanced isolation transformer. Thanks for posting the Decware IT link info above. I did not know Steve had ventured into this arena, though he has always been concerned about power quality. I am currently contemplating upgrading my speaker system P10 to a P20—thanks to PSA’s very generous upgrade policies—and also adding an Equi=Tech 2RQ. And I may add the Decware unit to my headphone rack where there are two P5s, and the Decware’s more modest capacity would not be limiting.

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Was that already in your brain? You, sir, are a pisser.