18w TMB Hum When Both Vol Pots Below 1.5

[Schlep]

PROBLEM SOLVED: Issue gone when chassis put in head cabinet. Didn't expect that.

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Hi All -

Hoping for some thoughts on a Mojotone 18 watt TMB build.

Amps sounds as expected except for one thing: When both volume pots for both channels (not the gain pot) are set at less than about 1.5 the amp emits a hum. When either volume pot is set beyond about 1.5, the hum goes away.

Never experienced this in any other amps. I'm figuring it is something minor as beyond this issue, the amps sounds and respondes as expected... it sounds pretty good : )


Thanks for any thoughts / assistance,

Craig

[Bieworm]

Hi there. When you say mojo, that means trouble. The problem is likely the layout and grounding details. Send the layout diagram and some detailed pics of your build. Let’s see what we can find there

[Schlep]

Hi Bieworm -

Thanks for your response, it is appreciated. Problem was solved when I put the chassis in the head cab.

Regarding Mojotone, I get it. They initially sent the wrong board, then when I ordered the head cab, there was something wrong with it and it had to be replaced. No more mojotone kits or cabs / heads for me. I purchases a kit because I had never built a marshall style circuit. I am familiar with the BF fender so I thought a kit would be a good place to start with a marshall. Everything is sorted out now and it does sound pretty good.


Craig