Robin 993DX

Hi gang,

I was wondering if there is anyone in the S. California area that would be able to help me diagnose and repair a vintage amplifiers? I have a 1960s era McIntosh MC250 amplifier that is having some issues with just the left channel. I have the schematic, block diagram and parts list.

The left channel basically just distorts whenever the volume is turned up, but in mono mode and low volume it works fine. I have done various test and swaps to know for sure that it is the left channel.

I just wanted to try my luck here to see if anyone on the board that's local to me can help me identify and repair the problem before I ship it off a cross the country.

Thanks

Paul902

McIntosh! Cool amp. Sounds to me that somethin is gone in the bias or an amplification stage on left channel. Sometimes volume pots get noisy but since it is fine loud mono or low volume this is probably not the case. Considering the age it could be a C or R gone bad. I've seen that before.

Paul

AnthemAVM

Why don't you talk to Kevin at Upscaleaudio.com, he can help you out.