M70 slight problem...what could it be?

[tygr]

I have an M-70 amp that sounded great for about 6 months after I purchased it. Now, however, there is a slight amount of distortion in the left channel. It started all of a sudden one day after powering up and hasn't changed or gotten worse on subsequent tries.

Any clues as to what could have died? Any help appreciated. I'm just trying to determine what the cost should be at the local repair shop. Thanks.

 

[avionic]

Dirty input attenuator or relay contacts possibly. Maybe a cold solder connection.

 

[Bratwurst7s]

Have you swapped the pre-amp inputs, and then the speaker wires, to listen if the problem moves to the right channel? Just to eliminate them from being possible culprits.

Cheers,
James

 

[tygr]

Thanks kids. Will give it a more thorough check.