I posted before, and I stand to correct myself. Experience begets experience.
Best tweak: dedicated AC. Optimize w/ a good outlet (how good? i'll let you know once i test).
The twisted pair 12*3 romex i put in (w/ audiophile approved outlets) has made a dramatic change in my system: low level details emerge that i never knew existed. bass is significantly tighter, deeper, and images. black backgrounds. and most of all: PRAT...which conditioners are oft to suppress---this is a revelation for my system, of which a 50wpc SET into WP6s is the heart: the percussives have impact that i never thought a SET could deliver (no doubt the transparent speaker cables also influence this parameter).
this was a wonderful improvement and i regret i never did it sooner.
