Ampeg VT-40 Short Box with Hum

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Ampeg VT-40 Short Box with Hum

Postby MikeF1227 on Mon Feb 06, 2017 5:00 pm

Hi guys,

I'm new to the forum, so I hope I'm not re-asking a question that's already been answered. I bought a VT-40 short box a few years ago and I've been loving it ever since. I've had some work done to it, new tubes, some electronics clean-up, and I did a lot of cosmetic work so it looks brand new. The speakers are Mojo Tone, which I'm going to replace at some point because I'm not entirely thrilled with them and want a more authentic sound.

The problem I've been having is a low-end hum. It doesn't change when I raise the volume level on the amp, it just stays constant and bugs the hell out of me when I'm recording. Is this a grounding issue? And if so would it make any sense to replace the standard two-prong power chord with a three-prong? I did have my local tech take a look at it a few months back when I was having some other sound issues, and he replaces a few of the tubes and I believe he did a cap job so I'm hoping that's not the issue.

I love this amp and I'd really love it to be in peak condition considering how much money I've put into it. It gives me everything I need and more.

Thanks in advance for the help,

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Re: Ampeg VT-40 Short Box with Hum

Postby Dean Jr. on Fri Feb 24, 2017 9:09 pm

IF the amp has original electrolytic capacitors, I suspect them.
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Re: Ampeg VT-40 Short Box with Hum

Postby Baron Von Machinenmann on Sun Feb 26, 2017 3:17 pm

+1 Most likely the power supply electrolytics, probably needs a good overall servicing as well.

Great amps in their own right, nice score! :thumbsup:

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