Hmmm, as you stated, it acts the same way from your 15 amp circuit as well as your dedicated 20 amp, yet works fine at Cary and your friends location(s) without the extension cord - when considering your friend's theory.
Jea48: As you know, "inrush" current is typically instantanious - with PS filter caps charged to 95+% within a few seconds, or so, for most high-power amps. Note he's stating the breaker consistantly trips "after 20 seconds", and even from several of his apartment's pre-wired standard 15 amp outlets. His recent noted voltage drop to 112, only at the moment of trip, is curious. For a thermo-magnetic breaker, you'd expect to see sustained high current voltage drop right up until tripping vs the virtually unaffected static 118 - as if the power supply wasn't even pulling current (?).
I just took a look at Cary's online PDF Owners Manual for anything of interest and there's not much to assist.
http://www.caryaudio.com/pdfs/manuals_2012/Model7.250_manual.pdf
Jea48: As you know, "inrush" current is typically instantanious - with PS filter caps charged to 95+% within a few seconds, or so, for most high-power amps. Note he's stating the breaker consistantly trips "after 20 seconds", and even from several of his apartment's pre-wired standard 15 amp outlets. His recent noted voltage drop to 112, only at the moment of trip, is curious. For a thermo-magnetic breaker, you'd expect to see sustained high current voltage drop right up until tripping vs the virtually unaffected static 118 - as if the power supply wasn't even pulling current (?).
I just took a look at Cary's online PDF Owners Manual for anything of interest and there's not much to assist.
http://www.caryaudio.com/pdfs/manuals_2012/Model7.250_manual.pdf