High Current Outlet for Amps?

" It depends on the class of amplifier, as randy-11 stated.  With typical class AB amp music power is very low, being only a few percent of peak power (unless you listen to sine waves). "

What about for an amp like my Krell FPB 400-cx, which I believe is class A?  Supposedly, you are supposed to have a 20 amp line, but I just plugged it into a regular outlet and it seems to work fine.  I do have pretty efficient speakers, however.   Considering that I don't play music or movies all that loud, will a 20 amp line make any discernible difference?

Krell recommends minimum 20A circuit. They specify 75W at standby, 350W at idle (whatever it means) and 3000W at max.  Pure class A amp would draw max power all the time, equivalent to 25A on 120VAC supply.
Outlets in my home are 15A style but all circuit breakers are 20A.  All outlets are wired with 12ga wires.  All light fixtures are wired with 14ga wire protected by 15A breaker.

Ground loops? 

@cleeds  

Commercial and Industrial 30 Amp Flush Mount Dryer Power Receptacle with 3-Wire Non-Grounding,

Dude...read what the quote above says...its a DRYER power receptacle.  All you do is hook up 10 gauge wire to a 30 amp breaker to a regular power outlet and you are good to go.

hifiman5

Dude...read what the quote above says...its a DRYER power receptacle.  All you do is hook up 10 gauge wire to a 30 amp breaker to a regular power outlet and you are good to go

What I showed you is a 30A outlet, which is commonly used for dryers, "dude." Putting a 30A breaker on a 30A line - but connected to a 20A receptacle, is a code violation, for the reasons I previously stated. It's a fire hazard.