Peavey Classic 30 Hum when increasing reverb amount

[Fantomaxit]

Hello All

I'm new and I want to say hello to all the members
I have a prob with my Peavey Classic 30.
As soon I increase the level of the reverb , I hear a 50Hz hum increasing
What can I do for eliminate it ?

Tnx

[TomCarlos]

Welcome....

Let's start with step 1 - making sure your cable ends are clean. The tank is connected with RCAs. Pull those out, make sure they are clean (on both ends). Also, put some spray cleaner on the RCAs and work those (left right) on the tank itself. We want to make sure you have no dirt or corrosion build up anywhere.

Is this a newer Classic 30 or an older model?

Tom

[tubeswell]

What's it like without the reverb on, but with the OD channel on and all the volumes up? Any hum?

[jmaf]

Hi Fantomaxit, welcome aboard.

Could be a bad tube, some grounding gone awol, dirt/oxidation on the reverb RCA plugs or anything that brings in mains frequency into the mix. Oxidation/dirt always makes grounding bad and bad grounding always pulls in mains freq.

There is no mains frequency anywhere in the amp unless it's tube heaters or the environment (wire dressing, transformer too close etc but in the Peavey Classic 30 it's almost sure a bad tube or loose/oxidated contact).

[Enzo]

Probably not a tube, as the reverb circuit is based on a 4558 IC.

[stokes]

Dont know if it applies to this amp but a common problem in Mesa Mk series was a bad ground connection on the rca jack attached to the chassis.