MM pre-amp on way out?

[stacker]

Early '90s MM, pre-amp suddenly started distorting badly. It's not the battery. The treble tone pot began behaving like it was dirty yesterday so I cleaned it with lubricant. Think that's a coincidence, though.

Any ideas? Sure it's pre-amp on way out.

 

[Selta]

Seems pretty odd, and unlikely that the preamp is bad. How did you rule out the battery? Did you also try different amp/cab and cable?

 

[Captain Chaos]

Jack?

 

[stacker]

Battery is fine; still reading 9v as was replaced recently. Other cables/amps tried; same effect.

Doubt it's the jack. This is nasty overdriven distortion which then sags before returning to it's initial level.

 

[murphy]

probably replace it with a Nordstrand music man preamp.....I did...and like the sound

 

[stacker]

Op-amp replaced and all good