Tube Experimentation: On/Off Cycling & Tube Damage

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Axemeister, Mar 20, 2008.

  1. Axemeister

    Axemeister Member

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    I wonder about all of the on and off cycling I am putting my amps through when experimenting with preamp tubes. Every time I pull and replace a preamp tube I am going through a shut down and restart of the amp. .. Then I test the tone and do it again. This leads me to wonder if I am doing too much wear to my other tubes through all of this power cycling. Is there any other way to do this??
     
  2. SatelliteAmps

    SatelliteAmps Member

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    Probably not doing too much damage. Most preamp tubes can be pulled and replaced while the amp is in standby.
     
  3. Axemeister

    Axemeister Member

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    Ahh, I have been afraid to pull the preamp tubes while they are glowing. I did not think that would be good for them..
     
  4. rockon1

    rockon1 Member

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    I replace mine with the amp on stand by however the cycling is worth it if you feel better about doing it that way. Im impatient and dont want to wait for the power tubes to heat up. Bob
     
  5. Faustine Amps

    Faustine Amps Member

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    Ditto! That's what I do. If the amp is in standby, you're only de-mating and mating the filament voltage. Not a big deal. Just make sure you're really in standby when you do it!

    Regards,
    Tim Gregoire
     
  6. EarlTX

    EarlTX Member

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    I looked into that at one time, and found out that one of the worst situations for tube life is heating and cooling them.

    Apparently, this causes the cathode material to expand and contract( naturally), and in the process, small bits of the material flake off. Eventually, it leads to less efficiency. At what point this becomes an issue is anybody's guess.
     

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