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SVP-PRO help!

I picked up a svp-pro. Two things have jumped out to me. Fisrt is I realy like the sound and tone of this thing. Second, it buzzes like mad! When everything is unplugged except the power cord and its turned on there is an audible hum noise. There is a slight vibration when you touch it as well that seems to match the noise. Is this tubes? I havent ran across this yet, have shows this week and need a fix. Thanks.
 
Yep, it is the tubes. The one I bought from Big Joe, had replacement tubes. I think that they were Chinese of some sort. Any way, it never hummed at all. Open it up and see what tubes are in there.
 
tubes are tricky animals. my guitarist had the same prob with his head a while back. tubes can be bad right out of the box even groove tubes. sometimes they get a bad batch.(no reflection on the ampeg)hell he even had some of the expensive american tubes go bad(they were brand new) don't feel bad it happens to every one and it's a quick fix. i don't know about ampeg but i had the same prob with a boogie. i called them and they sent me new tubes free. can't beat that.
 
inazone said:
When everything is unplugged except the power cord and its turned on there is an audible hum noise. There is a slight vibration when you touch it as well that seems to match the noise.
I doubt that the tubes are vibrating. Chances are that the power transformer is the culprit. My blackface SVP-Pro hums a little, but isn't a serious problem.

If it is new, you might be able to send it back. If it is used, see if it is something you can live with. 60Hz hum is annoying, but is not dangerous.
 
There does seem to be much inconsistency with Ampeg products. My SVP-Pro (retubed by previous owner, as I've mentioned many times :) ) doesn't buzz or rattle, and hiss is minimal at gig volume when no distortion used.

OTOH, the Ampeg SVT3Pro I owned until recently did sputter a bit while warming up (10 mins or so). When I first got it the hiss was more noticeable, but then someone here suggested burning in the tubes: that is, by leaving the amp on for 24 hours straight. I actually left mine on for over 48 hours, and by golly, the noise level did decrease significantly after that.

All that said, the problem with your SVP-Pro seems to be more than just the tubes. Good luck, and please review the SVP-CL if/when you get it!
 

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