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Tube rattle, buzz, vibrations, etc!?

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Doug Spears (douglasspears)
Username: douglasspears

Registered: 10-2008
Posted on Tuesday, November 25, 2008 - 07:14 pm:   

I'm getting a lot of tube rattle from some brand new winged "C" tubes....Russian made. Real bad. I bought this amp a few months ago, got new tubes b/c of the rattle, and it's almost worse now!?! Any recommendations of a good "non-rattly/low-rattly" tube?

Also,,,,,it read here on this forum that it's best to run 212 HD combo's on 4 ohms. Why? Rattle? Tube life?

Lastly, getting a lot of buzz from the amp....ESPECIALLY with the reverb tank wires (and the footswitch) connected. They seem to act as an antenna. Is that normal? This buzz is coming thru the speakers when nothing is being played....no guitar plugged in,,,nothing. It gets louder the louder I turn the amp. I can kind of even almost hear it thru the music when I'm playing!?!? Normal? Any way to ground these, or something?

I'm looking for a good MM tech in ATL, any recommendations?

Thanks!
Doug
Mike Kaus (mm210)
Username: mm210

Registered: 05-2006
Posted on Thursday, November 27, 2008 - 11:50 am:   

Tube rattle is a common problem, unfortunately, with newer production tubes. It sounds like you just got some bad ones. If you bought them from a reputable dealer and recently, they should exchange them. HUM-probably due REALLY bad for a cap job, unless it's been done. Shoulfd be done before you smoke the PT. I mean, it COULD be a ground problem but you would have to do some poking around to find out. Don't really know anybody in your neck of the woods though. Hopefully somebody else will chime in with a tech in your area. The combos were designed to run on 4 ohms in that era. Is this amp a tube inverter or SS? 12ax7 in the amp?
Doug Spears (douglasspears)
Username: douglasspears

Registered: 10-2008
Posted on Friday, December 12, 2008 - 07:15 pm:   

Thanks for the help Mike! I literally have tube rattle at every single note. Min eis SS, w/out the 12ax7. hmmm, I'm running on 8 ohms now, I guess I should switch to 4.

I did take it back to the guy...supposedly reputable (referred to me) but he said "oh well, tubes will do that". And when asking about my other questions, he said he would've charged more in the first place if he knew "I would be this picky". Huh? Thanks Jack Ass. Andrews Amp Labs here in ATL. I will not go back.
Giordano da Silva (macg1)
Username: macg1

Registered: 06-2009
Posted on Wednesday, July 22, 2009 - 03:49 pm:   

According to a amp repair book you can tension the tube sockets using a toothpick. I have done it before in vintage amps with excellent results.
jnewmark (jnewmark)
Username: jnewmark

Registered: 11-2012
Posted on Saturday, November 24, 2012 - 04:10 pm:   

A toothpick ? Wow, I'd like to see pics of that.
Mike Kaus (mm210)
Username: mm210

Registered: 05-2006
Posted on Sunday, November 25, 2012 - 07:11 am:   

Toothpicks WILL work but there is the risk of breaking the damned thing OFF down in there. I use dental picks and special little picks that we had for fixing small connectors in the automotive world were I came from. Mike.
David Goldberg (ddgoldberg)
Username: ddgoldberg

Registered: 07-2011
Posted on Sunday, November 25, 2012 - 09:27 pm:   

Speaking of tube sockets, here's a trick I found with my MM. While it doesn't make the tube sockets grip better, it does make for a much more positive contact and cleaned up all the background noise I had. Clean the tube pins and the inside of the socket connectors with DeoxIT Gold concact cleaner (perhaps another brand would work as well). I have a small brush that fits down inside the socket contacts and I scrubbed them out with the cleaner. I couldn't believe the audible difference.