Fabrication of box containing AC power meter, AC volts meter and AC amps meter with AC outlet and power cord.

[antcollinet]

A proper power quality meter with transient analysis is going to be many, many thousands of dollars. I'm not sure what y'all are really looking to measure but if you want millisecond-resolution a hand-held clamp on you bought at the Home Depot isn't going to get you there.

I don't think ms resolution is remotely necessary.

Even 1s resolution is not really that important when it comes to power consumption measurements. We don't need to know what a peak power transient is. Only what our kit is going to consume on average:

A - During normal music listening.
B - If left on in low power or standby modes.

 

[pseudoid]

Science is science. It's the method, not the tool.

A practicing scientist is nothing without the proper/accurate tools but must also have acuity in being able to properly use them.
"Almost" counts in horseshoes and hand-grenades... and possibly ghetto-made bombs. ymmv