Service Tech in CT/MA?

A friend has a non functioning mono block solid state amp. No schematic. Any suggestions on where to bring the amp for repair?
Thank You!!!!!
Giving us the brand and model may help find a tech.

I've heard positive comments but no personal experience.

You can always try Goodwin High End in Waltham, MA.
Approved Audio is good. Also try Electronic Service Labs in Wethersfield.
Cannot say enough good things about Approved Audio in Litchfield, CT. Larry is a supreme professional: smart, honest, reliable, very knowledgeable and has never let me down on repairs,alignments, rehabs, resurrections and diagnostics on tuners, CDPs, amps and speakers. Just absolutely tops. And turnaround is fast.