How is 10 awg wire not large enough for a 20A circuit? I cannot imagine a situation where using 8 awg wire reduced to 10 awg wire would perceptively "improve" sonics for equipment run through a 20A circuit. I have run two 95lb, 300 wpc, Class A amplifiers through two separate, dedicated 20A circuits fed with 10 awg wire and never had any reason to believe my power was adding distortion or restricting dynamics in any way.
Dedicated 20A circuits using one wire size up (i.e., 10 awg wire) is sort of the gold standard around here. Some believe further improvements can be achieved by powering all the equipment through a single dedicated circuit, or by using large isolation transformers, and of course some believe in pebbles and dust but, IME, if dedicated, properly implemented, 20A lines don’t meet the power needs of consumer audio equipment, the problem is probably with the equipment.
Dedicated 20A circuits using one wire size up (i.e., 10 awg wire) is sort of the gold standard around here. Some believe further improvements can be achieved by powering all the equipment through a single dedicated circuit, or by using large isolation transformers, and of course some believe in pebbles and dust but, IME, if dedicated, properly implemented, 20A lines don’t meet the power needs of consumer audio equipment, the problem is probably with the equipment.