Diagnose This.

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Jiffy_Jeff, Feb 22, 2015.

  1. Jiffy_Jeff

    Jiffy_Jeff Playin Tunes and Having Fun! Silver Supporting Member

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    So last night I am playing an outdoor party. Turn on my 65amps and let it warm up. Show starts and all is good. 2 songs in the volume cuts to a 1/3. After a short time it goes back to normal. Then cuts again. So i reach over and flip the master volume switch on and it does fine for the rest of the night.

    Tube problem?
     
  2. Trobbins3

    Trobbins3 Silver Supporting Member

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    Guitar or patch cable?
     
  3. Jiffy_Jeff

    Jiffy_Jeff Playin Tunes and Having Fun! Silver Supporting Member

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    Nope. Cables and guitar are good. It worked fine when I flipped the master volume switch on.
     
  4. J M Fahey

    J M Fahey Member

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    Ask the 65 amps guy.

    He'll be able to answer 100 times better than anybody here.
     
  5. kevmin

    kevmin Supporting Member

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    Dirty or defective switch?
     
  6. Blue Strat

    Blue Strat Member

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    The switch was flipped and tubes are being blamed? :huh

    It's an intermittent connection somewhere. Could be anything in the signal chain (pedals, guitar, cables), or any connection in the amp including that switch or anything that vibrates when the switch is "switched".
     
    Last edited: Feb 26, 2015
  7. GT100

    GT100 Member

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    Yes, but we all know that tubes are at or near the top of the list of likely suspects.

    Lloyd


    Sent from my iPad using Tapatalk
     
  8. alexandergj

    alexandergj Member

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    I had a similar issue with effects loop switching jacks. Need good, clean connections.
     
  9. TimmyP

    TimmyP Member

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    My guess is that the MV switch is a double throw, and one side is dirty. "Exercise" the switch a handful of times and see if that cures it. Or it could be a duff joint or broken wire.
     
  10. NielsM

    NielsM Member

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    Agreed. Don't think it's a tube problem.
     
  11. RussB

    RussB low rent hobbyist Silver Supporting Member

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    Not in this case.
     
  12. Peteyvee

    Peteyvee Premium Platinum Member

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    That switch would be at the top of my list.
     
  13. 3gabe

    3gabe Member

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    What gets bypassed when you flip the master volume switch? Probably something there.
     

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