Strange metallic noise in my amp mid-way through a show

Discussion in 'Amps and Cabs' started by Deville2Rocket, May 25, 2008.

  1. Deville2Rocket

    Deville2Rocket Member

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    Was playing an outdoor show with my Ampeg Reverberocket last night. The amp was cranked good n loud. I have 6V6's in it vs. 6L6's.

    After about an hour or so of loud rockin', I began to hear a strange, metallic, kind of ringy sound when I'd play. Almost sounds like maybe a microphonic tube.

    What I'm wondering is do you think the biasing for 6L6s was too hot for 6V6's at very high volumes? Did the amp blow my tubes? I noticed my clean tone began to suffer, sounding unpleasantly dirty.

    What could have happened?
     
  2. SatelliteAmps

    SatelliteAmps Member

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    It could have just been a tube going microphonic. Was the amp biased and set up of 6V6s? If so, then that shouldn't be a problem. If the amp was set for 6L6's and you threw in some 6V6's that would be a problem.
     
  3. Deville2Rocket

    Deville2Rocket Member

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    Yeah, I never re-biased it. So you think the hotter biasing hurt the 6V6's?
    I don't really understand the cause and effect of hot/cold biasing. If the bias was too hot, is it likely I killed my 6V6's?
     
  4. Deville2Rocket

    Deville2Rocket Member

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  5. Roccaforte Amps

    Roccaforte Amps Member

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    If it isn't a speaker voice coil rubbing, it's an output tube rattling
    on low notes.
     

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