Rectifier tube in '71 Princeton?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by 56_Special, Jul 31, 2006.


  1. 56_Special

    56_Special Member

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    Does anyone know whether a '71 Princeton uses a GZ34 or a 5U4GB? If it uses a 5u4GB, what current manufacturer makes one?

    Best,

    Martin
     
  2. wilder

    wilder Supporting Member

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    As far as I know it could be either in 71. I presume there's no tube chart? What was in there already? A NOS 5U4GB should run about $25 so I don't know what to look for in a mondern one.
     
  3. Blue Strat

    Blue Strat Member

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    5U4GB for sure, though the plate voltage is often low enough that a 5AR4 can be used.

    With NOS 5u4GBs (which typicallly last 30 years) at $20 a pop, I can't imagine why you'd waste $10 on a POS Russian one.
     
  4. 56_Special

    56_Special Member

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    Doh, the tube chart! :jo THis is my first fender amp, and it didn't even occur to me.

    Thanks for the info, Blue Strat.

    Martin
     
  5. Blue Strat

    Blue Strat Member

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    Often, the tube charts are not correct. Fender kept using the older tube charts until they ran out, even after rectifier tubes changed from 5AR4s to 5U4s. Guess they figured that all the other tube positions were ok so why bother printing new charts just yet...
     

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