Originally Posted by whoaru99
And yes, a 20A breaker and receptacle is plenty unless you plan on bench testing continuous rated power using with test tones.
In hindsight, the upsized 30amp wiring, combined with a 20a breaker, and 20a receptacle, would've been fine.
If they're robust enough, amplifiers can pull extraordinarily high amounts of current from the wall, due to typical circuit breaker trip curve characteristics.
To allow for the very high currents inherent to motor start up, etc, circuit breakers will pass enormous amounts of current past their normal rated size. For example, a 20 amp circuit can pass 7-8 times the rated 20amp trip amount, .. for up to a second or more
. It will allow up to 3x the rated amount for up to 10sec
or so. And most importantly, the same 20amp circuit, can allow up to 1.5-2times the rated amount for a period extending as long as 30 seconds.
That's over 100amps for around 1-2 seconds, about 60amps for around 10 seconds, and the circuit will allow 30-40amps for as long as 30 seconds! From a 20a breaker.
This is why voltage drop, and ample current delivery for instantaneous peaks can be an issue. Up-size those amplifier/subwoofer circuits. Not the breaker size, upsize the wiring. As I illustrated above, the breaker isn't the limiting factor for our uses.