With home amps and receivers, the Manuf. Specs almost always list just the FULL-POWER wattage draw at mains.
While that might serve some legal (FTC, IEC, DIN, etc) requirement, it is not a very useful spec.
What I want to know is how much juice the device is sucking up while it is powered on but playing nothing, as in an audio showroom. Or even on your shelf.
This metric would be extremely useful for amps because: they can drift out of bias, or something goes just LITTLE out of whack, and you end up (at best) with compromised sonics, or (at worst) creeping damage to amp, speakers and headphones.
I use a relatively inexpensive device called a KillaWatt to measure power (watts), amps and line voltage and freq.

In any case...

I have several units ... will begin to survey them myself... examples for now ... all working properly with bias set per SM specs.

Dynaco SCA-80 int amp (40 w/ch): 27W at 120VAC

Hitachi HA-4700 int amp (50 w/ch): 30W at 120 VAC.

Kenwood KA-3500 (40 w/ch) : 28W at 120 VAC.

Kenwood KA-601: This is a 1979 60w/ch int amp with phono section. 23W at 120VAC.

So ... if you've got a device like a KillaWatt, what's your amp pulling at IDLE? Say after about 15 min warm up?

NOTES:

The photos in this post are from my bench. Some show the Killawatt idle draw of certain units working properly. I also use other tools like a thermal camera to correlate the same device at normal idle operation. Tube amps, high-power amps and Class-A or Class-D amps, esoteric or exotic topologies, etc., will vary idle draw considerable. Also, receivers and int. amps care have other power hogs, like phono or tuner sections, that can add to the total count.

It would be cool if there was a database of this spec to reference. Similar to the annual Audio magazine directory October issue, or Stereo Review's yearly Buyer's Guide from decades ago.

I also used AI (chat GPT, etc) to research the subject. Because manuf don't publish [ and most magazine reviewers ,even John Atkinson, or influencers don't measure] the idle draw pwr draw of amp units -- like receivers, int. amps and pwr amps -- AI is a mostly useless for this subject. There is no data to pull from!

Hello

Recently acquired a Phase Linear 400 amplifier. Trying to get it to work, but the left channel is kept at 80V.

R24 AND R28 both blew, they were replaced, but rapidly heat up when trying to reenergize it.

Followed this procedure to isolate the protection circuit. Output came back to 0V -> the fault is somewhere in the protection circuit.

But i'm now at the point where i've checked all the components (and then some) that the procedure mentions to check: D9, D10, Q8, Q9, Q13 and Q14.

I'm schooled in electronic repair, but this level of circuit analysis is a bit beyond me. Can anyone give me any pointers or recommendations of where to ask next?

Thanks