The issue in AC powered audio equipment is usually leakage-to-ground. This is caused by, among other things, inter-winding capacitance in the power transformers and capacitors in mains-entry filters. In the "old" days, when everything was connected using 2-prong mains plugs, sometimes one could empirically determine the best direction to orient the plugs in an audio system with multiple mains connections.
In today's equipment, if it is properly designed, the overwhelming majority of the leakage current should be conducted through the third-wire ground on the mains plug, not the audio grounds interconnecting the equipment, so "polarity" of the plug becomes much less important from a standpoint of leakage. That said, I usually try to ensure that all audio equipment in a system is connected to the same side of the neutral, rather than have it split across the neutral, thus minimizing the potential leakage current. Back when I used to do PA for live bands, I used to carry a couple low-leakage, medical isolation transformers with my PA rig to deal with leakage and hum problems in guitar amps. Some guitar amps were designed so bad that the guitar player, with his hands touching the metal strings, would get a shock on his lips if they touched the metal windscreen cage of the vocal mic. A medical isolation transformer always fixed that problem, as well as the hum it usually caused. -- Timothy Stockman ------------------------------------------------------------------------ Timothy Stockman's Profile: http://forums.slimdevices.com/member.php?userid=8867 View this thread: http://forums.slimdevices.com/showthread.php?t=45195 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
