Zapco mono amp $150 ?

https://www.ebay.com/itm/Zapco-ampli...4AAOSwUMpd7PWd

Zapco DC Reference DC 500.1 [open box]

That amp hasnt been in production for 10 years or so. its a good amp tho

Somehow there's still lots of those zapco DC amps "new" on ebay for cheap. Pretty highly regarded from some experienced users on the other site. If you only need 500 watts why not buy one for 150

I'll agree. Had a few of those DC amps, and they were rock solid. Sounded very clean and good.

But, if you want to use the software for tuning - good luck.