Bench testing amp

Most EE techs that build their own amp/s or even good ones that repair, should be able to help you out with most if not all bench test measurements.
I don’t know where they are, but these guys have one of the most advanced detailed bench testing setups for audio, even more than Stereophile, if you have a login password you’ll see what I mean.

http://www.milleraudioresearch.com/index.html     Click the AVTech Tab

Cheers George

Not sure how close you are but I hear John Atkinson is pretty good.