I ran the audio side of my home theater setup (2 Adcom 555ii amps for sub+center and Orion bass drivers in parallel (2.5 Ohm minimum impedance); 4 Adcom 555ii amps for Orion mid + tweeter; Lexicon processor; the usualy HTPC for DVD playback and analog scaling; Marantz 7C for 2-channel; etc.) off one 20A circuit.
Plus the can lights (6x75W flood lamps, 4x65 narrow).
While the peak current consumption can be pretty hefty (spec'd at 42A just for my amplifiers) without running big class A amps (or maybe really small sub-woofers where physics dictate horrible efficiency) there's no way you're going to get average levels high enough to cause problems during normal listening (90-95dBC average SPLs listening to rock music, reference level home theater with peaks to 105/115dB from full range and LFE channels respectively).
Plus the can lights (6x75W flood lamps, 4x65 narrow).
While the peak current consumption can be pretty hefty (spec'd at 42A just for my amplifiers) without running big class A amps (or maybe really small sub-woofers where physics dictate horrible efficiency) there's no way you're going to get average levels high enough to cause problems during normal listening (90-95dBC average SPLs listening to rock music, reference level home theater with peaks to 105/115dB from full range and LFE channels respectively).