Two tube power amp designers/builders who say yes are Tim de Paravicini (EAR-Yoshino) and Roger Modjeski (Music Reference). Roger will personally hand wind you one for $1,000. Tim says he can tell you how an amp reproduces bass by looking at the transformer.
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ptss---The DIY guys who build their own amps are the ones to ask about transformers. They all have their own personal favorite(s), but you see the name Magnequest a lot. rcprince is right, the Jadis transformers are really nice, but proprietary---you can't get one (without buying the whole amp!). Give Modjeski a call---he's pretty open about recommending stuff like that.
If the transformer is not wrapped with low frequency high permeability mu metal sound quality will suffer. No two ways about it. The toxic effects of the induced magnetic field extends to everything within what, about a foot of the transformer? At least.
Magnetic field outside of toroidal transformer is theoretically zero. It is completely contained inside of the core. Toroidal transformer has no gaps making it more sensitive to presence of DC voltage.
"Magnetic field outside of toroidal transformer is theoretically zero. It is completely contained inside of the core. Toroidal transformer has no gaps making it more sensitive to presence of DC voltage."
Theory doesn’t seem to hold for a lot of things in audio. I wrapped a toroidal transformer, the aftermarket transformer in my uber modded Oppo 103, and heard good results. Maybe it doesn’t take much leakage to be audible, who knows?
"if the transformer is hand wounded using high quality silver wires with iron-nickel alloy in Double-C configuration, will this give deep bass without compromising the highs and still sound quick & agile?"
I imagine that combination of metals would work rather well since, you know, iron-nickel alloy is mu metal. I suspect it would sound like a million dollars.
I had several encounters with the late great James Bongiorno (Hadley, S. A. E., Great American Sound, SUMO and Spectra AmpZilla fame) who would agree that transformer design and quality has a significant effect on the sound of an amp. His very own amp designs testify to that. Look at the old Ampzilla, Son of and Grandson amps, all having huge high quality transformers.
He told me that the transformers were one reason that old Sansui receivers and amps sounded so good. At the time I didn't agree with him as I wasn't a huge Sansui, GAS, or SAE fan. My how things change.
I came to realize and appreciate what genius he was, and that more often then not everything he said was true. All of his designs are musical and engaging as was the man.
Two tube power amp designers/builders who say yes are Tim de Paravicini (EAR-Yoshino) and Roger Modjeski (Music Reference). Roger will personally hand wind you one for $1,000. Tim says he can tell you how an amp reproduces bass by looking at the transformer.Another couple designers (one already mentioned) who think alike are Kondo Audio Note Japan & Convergent Audio (CAT).
For tube amps the bigger the xformer the better for its bass. In the CAT JL2 the output xformers are 55lbs each (which contributes to the total 180 lbs) & CAT also winds his own xformers.
In s.s. amps the quality & size of the power xformer is important. Shielding the power xformer to attenuate the noise has a big effect on the amp's micro-details. Plitron makes some very good low-noise toroidal xformers. The size of the power xformer has much to do with the max output current of the amp's output stage which in turn has an effect on how difficult a load (speaker) that amp can drive.
Monolith Magnetics makes some very nice (and expensive) transformers. The OPTs I use in my 833C SE amps weigh 62lbs each, with amorphous double-C cores and virgin teflon interwinding insulation. Here's a picture of one during its construction.
They're not cheap but high quality very rarely is.
Another factor in transformer selection....
I’ve made seperate power supplies with large transformers for a few components and each time the improvements were significant - well worth the investment. And that was simply increasing the size of the transformer.
Factor in the other advantages listed above and you can see why good designers consider transformers crucial to good design.
williewonkawilliewonka, what you have written is simply bad information i.e. not correct. Please don't write incorrect material & misguide the public. it does nobody any good. Your conclusion to use a large xformer is correct tho'.
The transformer does *not* act as a reservoir of energy. That is the job of the power supply capacitors. Capacitors store charge & if there is a transient in the music, it is these power supply caps that provide the burst of current needed by the amp. The transformer is a conduit for providing current to re-charge these power supply caps. The larger the power xformer, the more current it can handle & the faster the power supply caps re-charge ready very quickly for that next transient in the music.
A small trasformer is unable to provide all the energy and as a result there is a tiny drop in the circuits internal voltagenot correct - a very small transformer cannot handle large currents hence cannot re-charge the power supply cap quick enough. So, the power supply caps suffer a droop in voltage for much longer a time than if a bigger, higher current xformer would have been used.
The voltage fluctuations degrade the amps output signalcorrect. it is called amplitude modulation (AM) of the music signal which is a form of distortion due to a badly filtered power supply.
The Bigger the transformer, the better the amp is able to handle the demand for electrical energy, fluctuations are minimal and the result is better quality musicthe conclusion is correct but the bigger xformer is *not* why the fluctuations are minimal. The fluctuations are minimal due to the power supply caps filtering/suppressing power supply ripple. IOW, you could use a very large power xformer & have no power supply caps & you would have huge power supply ripple which would destroy the quality of the music.
Bombaywalla - my apologies - the post was poorly worded.
I was attempting to use metaphors that people without detailed electrical backgrounds could relate too - I obviously failed.
My intention of using the "reservoir" metaphor was to communicate the fact that every transformer has a finite power delivery capability and not that it actually "stores" electrical energy like a battery or capacitor
But, just like a battery - If you exceed the delivery capability of a transformer, then things will happen at the output terminals of the transformer that then leads to degraded performance of the rest of the power supply and ultimately the entire component.
Designers of quality components understand the transient nature of audio and design sufficient "capability" into their transformers to deal with them, taking into account...
Components built to a "price point" often have power supplies that use a transformer conforming to a more "standard design" which are often less able to match the transient demand that the rest of the circuitry is actually capable of achieving and therefore results in the component operating at a reduced level of performance.
E.G. - I 've had a couple of components that used an AC Wal-Wart "power supply" and simply replacing the Wal-Wart supply with a "more capable" transformer elevated the performance of both components significantly.
For me - Good component design starts with the transformer.
I just hope I've redeemed myself - a Little at least :-)
thanks much for your clarifying post. Yes i believe that you have done well to redeem yourself. My apologies too for coming down on you so hard. I could have phrased that better myself.
It's hard to know how technical the audience is when trying to explain some this material. I've found that watering it down to suit a non-technical audience can add more ambiguity & confusion rather than stating it in a technical way & later on, based on the questions from the audience, explaning certain sections using more layman analogies. More often than not the audience here at Audiogon is pretty technical & they can stomach quite a bit before barfing but one never really knows...
Your last post shows you clearly understand the virtues of a good transformer in the design of a component....thanks.
Good info guys. There are many parts in audio designs that can impact the sound. Ps caps trannies resistors etc. polite on makes good tram
nsformers as I repair counterpoint products. Significant change in sound not always but yes. If the power supply is poor then I would not waste my time. The dad I build has a better powers supply that most amps I see. Happy listening.