I suppose these folks don’t want to know that utility transformers transmit noise both directions, so this doesn’t do much. It may help isolate from noise that comes from the audiophile’s house, though — nasty current waveforms will cause noisy voltage drops in the house’s wiring, and that will cause nasty voltage waveforms in the house (and everywhere else on the block, but less so).
A much better approach would be to buy a motor-generator pair with a decent-sized flywheel.
But this is all silly. The noise in question might cause audible noise in the power supply, but the power supply can go in a different room. As anyone who has listened to a problematic audio system can attest, the noise that really matters is the 50/60 Hz AC hum, and none of these hacks will help.
A much better approach would be to buy a motor-generator pair with a decent-sized flywheel.
But this is all silly. The noise in question might cause audible noise in the power supply, but the power supply can go in a different room. As anyone who has listened to a problematic audio system can attest, the noise that really matters is the 50/60 Hz AC hum, and none of these hacks will help.