Transformers have no effect on sound quality. That simple.
I suppose, you are joking.
I just tried to change the toroidal trafos in my monoblocks.
Both ones have the same electric / physical parameters; but made by different brands.
One pair is Talema/Nuvotem; other pair is Noratel.
300VA each.
Some years ago I changed them because of the hum; now I inserted back the originals to check the sound/hum.
Hums are almost the same... a light difference, yes, really. Not very suprising.
Sound?
Enormous difference.
I can not produce this overtones-deviation via my 2k $ speakercable vs. 10 $ pure wire.
So, that's why I feel a small free area here to get a better sound.
Anyway, I see a little conspiration about toroid-glorification. The size and efficiency and field-insultation is OK. Brands know it very well; it's a serious economical question.
But what about the sound? I don't know yet.
If you show the toroidal winding system to a 6 years child, she/he will say 'Sunny'. Yes, there will be radial gaps always. Always. No solution; it's a geometrical issue. The old EI and the newer R has independent and no-gap wiring.
Some thoughts:
We all tend to over-spec transformers for DIY builds. My NCC200 based amp uses a pair of 250VA 25/0/25 transformers for essentially a 60W/ch rms output at full chat. If the amp is idling along at say 0.5-1W nominal output with transients of say 10-20W, then with bias currents etc the supply is only delivering say 5-6W typical for most of the time. Is it possible that what some hear with different transformers is the effect of partial saturation in the core at such low supply (transformer) loading? Do say Canterbury Windings transformers have a larger core than 'XYZ' transformer for the same VA rating? If so, that will probably 'get out of saturation' at a lower supply loading than 'XYZ' transformer?
Some thoughts:
We all tend to over-spec transformers for DIY builds. My NCC200 based amp uses a pair of 250VA 25/0/25 transformers for essentially a 60W/ch rms output at full chat. If the amp is idling along at say 0.5-1W nominal output with transients of say 10-20W, then with bias currents etc the supply is only delivering say 5-6W typical for most of the time. Is it possible that what some hear with different transformers is the effect of partial saturation in the core at such low supply (transformer) loading? Do say Canterbury Windings transformers have a larger core than 'XYZ' transformer for the same VA rating? If so, that will probably 'get out of saturation' at a lower supply loading than 'XYZ' transformer?
Tube OPT cores are extremly sensitive area; why should we think that PSU transformer cores have less importance?
Lower distortion seemingly with your torroids...The measured bandwidth of the toroids was quite a bit better, which resulted in less overshoot on square waves. The toroids could also manage slightly higher power output due to their lower losses. The turns ratios were identical.
BUT... the "valve magic" had gone when we auditioned the amp fitted with the toroids
Well, for one thing..
...tube OPT have to carry the full audio signal - a very wide frequency range - 1000:1 to cover 20Hz - 20KHz for instance.
The PSU transformer? - 50Hz only.
The PSU transformer? - 50Hz only.
Naim claims that a low impedance transformer will result in better sound because the smoothing caps charge faster and therefore the conduction angle is smaller.