Anybody want to help troubleshoot my guitar amp?

[MitchSchaft]

I own a Hughes&Kettner Attax 100 guitar amplifier. It's had this problem for a while, but I'm just now getting around to trying to do something about it. Ok, this amp has 1 tube for the pre-amp part of the amp. Now, no matter what the volume level may be or what effects are hooked up to it, the volume will kind of adjust itself. I will be playing and it will go up and down for no reason at all. Anybody hear of this or have any suggestions?

 

[Platypus]

Sounds like your tubes are broken

 

[4824guy]

Yes it could be the tubes. The tubes start performing wacky when the get older, worn, or start going bad.

 

[MitchSchaft]

Well, what does a tube look like if it's fubared? It only has one tube for the preamp and it looks fine. I was thinking that was a possability, but I have my doubts.

 

[MitchSchaft]

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[misle]

If the volume is changing it most likely is either a pre-amp tube going out or a bad transformer. Most likely the Pre-Amp tube.

If your amp is still under warranty then H&K should fix it for you. Otherwise, you'll have to replace the tube. Tubes don't look different when they go bad (unless they burn up).

Check your manual or H&K's website, but most likely you'll need a 12AX7 pre-amp tube.

I recommend a JJ / Tesla 12AX7. Good tubes for $10.

Good Luck. (check your warranty info! you don't want to void your warranty by digging around in your amp.)

 

[MitchSchaft]

Just the reply I was looking for. I really appreciate it, bro! I bought this amp back in '94 or '95, so the warranty is long gone. I've had this problem for a few years, but never bothered with it. I couldn't see why it would be a transformer problem either, but I'll buy a tube to see what happens. It does take a 12AX&/ECC83 according to the manual. Thanks for the tip. Any other suggestions? This amp has an effects loop built in. I just read it's not good to put a distortion pedal in with the effects loop. What do you think about that?

 

[MitchSchaft]

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[MitchSchaft]

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[Platypus]

<< Sounds like your tubes are broken >>



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