True. I guess I'm probably incorrectly assuming he has an array of stereo installation wiring around his garage and would just use the right size off the bat.

Also, while the continued whine noise may not necessarily mean a component is broken, but just that it sucks! I had an Audio Control EQ / Crossover in my last car for about two weeks. Tried common troubleshooting and finally did what I called out above. Still got the whine. Went back to the shop and traded it for a new Phoenix Gold piece. Worked right away in bench test, worked perfectly once everything was reinstalled. Guy at the shop didn't seem surprised, gave me the impression it wasn't the first Audio Control piece that had come back in for just that issue.

So yeah, you're right, bench test + whine not neccessarily = bad part. Maybe 95% , but no guarantee. Sure would be a lot easier to troubleshoot a bench test though!