Whenever i plug my yamaha to my SVP-pro if i dig in too much my amp starts super hi and shreding distortion is it possible that i need to replace a tube, or all of them? how can i spot whats wrong in this preamp?
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TUBE input: when to change them???
- Thread starter vene-nemesis
- Start date
It is possible your problem MAY be tube related, but generally preamp tubes last longer than you do. Take your preamp to a tech.
Turn down the input gain on the preamp and control your attack. It sounds like, ya know, distortion, to me.
It sounds like it COULD be a microphonic tube. Theres a real easy way to check. Take the cover off so you can see the tubes. Power on the amp and let it warm up. Take a pencil or chopstick and tape each tube gently. Youll definately notice if one makes a bunch of noise if you do it, its a bad tube and swap it out.
Just for the record, theres no reason to take preamp tubes to a tech, unless your super uncomfortable around that stuff. They dont need to be biased, unless theres some power tubes in there, which i dont beleive there is. Im guessing those are 12ax7's in there.
Just for the record, theres no reason to take preamp tubes to a tech, unless your super uncomfortable around that stuff. They dont need to be biased, unless theres some power tubes in there, which i dont beleive there is. Im guessing those are 12ax7's in there.
I believe it is 4 12ax7 and 1 12au7.
For the other posters the problem for me is that it sometimes stays that way you know amplifiying with that distortio, but if i tap the preamp with my hang a little bit hard it stops... you know the good old trick to fix TVs....
For the other posters the problem for me is that it sometimes stays that way you know amplifiying with that distortio, but if i tap the preamp with my hang a little bit hard it stops... you know the good old trick to fix TVs....
Noise through the speaker, sorry of course its gonna make a tapping noise, sorry that was an unclear post on my part. Youll hear a pretty horrible noise through the speaker, for this reason keep the volume pretty low. People always ask, how will I know? You will know if you have a microphonic tube, trust me.
tapped each one for like 1 minute and no i have n microphonic ones...
BTW i just realized that this jerks from ampeg mixed both sovtek and groove tools tubes how bad is that?????
BTW i just realized that this jerks from ampeg mixed both sovtek and groove tools tubes how bad is that?????
No worries about mixing brands of tubes, as long as they sound good to you they're fine. The tubes in the 12ax family are self-biasing, and they don't need to be matched.
