Why not possible? The difference is not subtle actually.
No OK Hi-Phibian. I meant literally, since I do not own a Thorens 150 or Linn. But you meant in general, even with my turntable - I get that. That would be comparatively easy for me by constructing my own crystal controlled 220V 12W power module. But would it prove anything? I can vouch that I have watched turntable spead with a stroboscope - it keeps rock steady for much of the time (a strobe would show up a 2% variation easily). Any frequency variations in the mains are long term here.
Regarding other claims of 'music character improvements' .... the result can only be that should I not experience that, you would/could blame either my amplifier or my hearing, and nothing would have been achieved by such a subjective exercise. For my amplifier I can modestly vouch (just for the record) that it out-performs anything in its class (some 80+80W output), and as for my hearing, I have already admitted that it is sadly limited to about 5kHz bandwidth for the right ear and 7,5kHz for the left ear, also with a varying 7 dB loudness discrepancy. You did in the past compliment me on that even I would experience the alluded difference in sound quality, but I dont really think so. There are enough practical examples out there to support this.
NOT particularly directed at you, Hi-Phibian, but I respectfully think many members should read more about hearing characteristics and the massive acousto-medical research done in that field to bring them down to earth a little - I have mentioned that before. But that is another topic.
