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Hi.
"lose in drive" - drive WHAT ??
Not many audio guys know the pitfalls of audio line transformers when used in many hi-end brandnamed passive linestages:-
(1) phase errors;
(2) low & high frequency roll-off due to limited winding inductance
& inter-winding capacitance respectively.
(3) dynamic range & harmonic distortion compromise due to the use of type of magnetic core;
(4) input/output impedance change with the transformer volume tapping selection;
(5) magnetic noise due to audio signal induction by magnetization of the core.
Etc etc.
Take example of phase error which is UNavoidable as the inherent nature of any magnetic device.
(1) At low volume, say -43dB, flat low bass response; phase shift -
1 degree@10Hz;
(2) At mid volume: -20dB, 0.3dB drop@10Hz, phase shift 9.6 degrees@20Hz;
(3) At full volume: 0dB, 0.5dB drop@10Hz, phase shift 12 degrees@10Hz !!!!
Frequency response of a line transformer drops at both ends depending on the receiving load, e.g. input impedance of the power amp. Ideally, most linear for infinity load !!! Higher the better.
Tube power amp is much better than solid state amps which generally get out 100KR or so - rather too low.
That is one way to explain why Art found the Bespoke passive amp was shy in its "drive" as he apparently used it to drive solid state power amps.
On the contrary, resistive volume attenuator is much more frequency response linear, next to zip phase error & less costly for sure.
That's why I full agreed to what Adrianlau's response to Art Dudley's review of Bespoke passive linestage (only USD12,000) in Sept 2016, recommending resistive attenuator instead considering he was a veteran magnetic volume control users for 15 years or so.
Also, why the Bespoke new model tags for USD23,400 so much more in only 6 years ???? Silver winding transformers, silver inster wiring ?
I am happy in adding a straight-line bypass to my active lines gave by using only silver plated oxygen-free pure copper wires of fast speed computer grade. Straight-line bypass as recommended by J Gordon Holt. Driving my tube paper amps - plenty of DRIVE !!
Jack L.