Marshall Jtm 60 615 Trouble

[Tuncay]

Hi bros!

I have got a problem with my Marshall Jtm 615 amp.

Yesterday when i was playing my guitar through this amp, suddenly volume is gone and amp started to make noise that like old fridge.

Power valves are new but preamp valves are old.

Please someone can help me out?

[mere4m]

bluemushroom

I'm not pro amp repair tech but have fixed many amps over the years!

Try inserting patch cable in the effects loop in the back there are two: series and parallel, try both, this is common issue with this model.

The two jtm60's I repaired where cold solder joints on the input jack and intermittent volume drop caused by dirty eff's loop jacks.

Hope this helps!