yamahammers

Thanks Christautosound,
I appreciated your input. I read somewhere the M series amps might have a problem with the power supply burning up. Have you heard anything like that? What do you know about the MX series of Yamaha amps? Thanks,
Orlando

not much similarity at all.
the M-50 is two generations older and considerably less power.

the M-85 had dual power transformers and made about 300 wpc while the M-70 was a carver licensed switching and triac controlled design.