High Current Outlet for Amps?

ptss.

.. I had a local licensed electrician come to my home and measure current draw to my amp & preamp with my system powered up while i listened to rock and classical orchestral, with my approx 88 db efficiency speakers and 200 watt amp, at levels higher than I care to listen. His measuring device didn't exceed approx 3 amp draw. I used 10 gauge wire and a 20 amp fuse. I did not sense any problem. Is this unusual?

Frankly, no, this is not especially unusual. A 3A draw does seem a little low, but perhaps your amplifier is especially efficient, such as a Class D design.

hifiman5

All I’m trying to convey is that the outlet for a 20A or 30A device is the same. The difference is in the gauge of the wire running off your electric service and amperage rating of the circuit breaker in your house’s electrical service box

No, a 20A receptacle (device) does not have the same configuration as a 30A receptacle, just as the 20A receptacle differs from the 15A version. This is intended to prevent a 30 appliance from being plugged into a 20A line, which could result in overheating and fire.

Here is a pic of a 20A receptacle
Here is a 30A receptacle.

Another difference is that a device rated for 30A should be capable of safely conducting 30A of current. There is no assurance that a 20A device can safely conduct 30A of current.

If you use a 20A receptacle, it should be connected to no more than a 20A breaker.

" 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?