Vintage Princeton Owners..Would you do the PI mod?

Discussion in 'Amps and Cabs' started by Axe_78th, Jun 3, 2008.

  1. Axe_78th

    Axe_78th Member

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    Just picked up a 66 non reverb Princeton in near mint condition. It sounds very good too. I have a buddy with a 68' Silverface PR who got the phase inverter mod and he said it made his amp almost as loud as a Deluxe. I would love for mine to be louder but it's so clean and completely original I hate to mess with it or devalue the amp. I realize the PI mod is reverseable but I'm thinking it would still lower the value?
     
  2. Jeffj

    Jeffj Supporting Member

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    DO IT!!! I am the type that does not prefer mods, etc. on Fender amps....I just like to leave them stock & use them as designed. However, I recently picked one up with this mod & I love it. It has a fixed value & the ground switch was used. Much more volume & it does get it into Deluxe territory. Makes the quite Princeton much more usable. Plus, its reversable, etc....I plan to have my stock one done as well.
     
  3. mark norwine

    mark norwine Member

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    Getting that extra power is not without cost. The "cost" is the increase in current being drawn from the power transformer & the associated heat rise.

    These puny little transformers are already at their limits, IMO. I've seen these 2 PR mods (aka "Stokes Mod and "Paul C" mod) eat power transformers, especially the Stokes mod.

    I can no longer recommend these mods....especially the Stokes mod.
     
  4. Lance

    Lance Member

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    Hmm, I have a 65 PR, and it sure seems plenty loud for my 5-piece rock band. In fact, I was getting a fair amount of stink eye from being a bit too loud. But, if you need a bit more juice, then I say, "Go for it," too.
     
  5. Jon C

    Jon C Silver Supporting Member

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    I usually listen to Mark about things like this so I have left my 65 PR alone & love it just as it is.
     
  6. Lance

    Lance Member

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    Good to know. Even though I was completely satisfied with how it sounded already, and would never even consider doing anything beyond a speaker swap. BTW, mine sounds just lovely with a newly released Tone Tubby. I have one of the prototypes of the San Rafael 25, and just love it!
     
  7. GuitarsFromMars

    GuitarsFromMars Member

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  8. cander328

    cander328 Member

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    No mods for my '65 Princeton Reverb. Just decided to get a few different sizes and hues of blackface goodness!!

    [​IMG]
     
    Last edited: Jun 4, 2008
  9. Jeffj

    Jeffj Supporting Member

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    Are we talking about a Princeton Reverb or a Princeton? Volume wise they are TOTALLY different. The original post was about a Princeton. I am not gonna argue the point about whether it is good\safe for the transformer . I am far from an amp tech & take Mark's word on it.
     
  10. Axe_78th

    Axe_78th Member

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    Well in a non reverb there are only two preamp tubes pulling heater current. However the info here explains to me why Fender designed the phase inverter as it is. Changing the amp from cathode bias to fixed bias has to change the tone somewhat I would think.
     
  11. yakyak

    yakyak Supporting Member

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    I don't know if the volume between a Princeton and Princeton Reverb are really all that much different. I contend that the tone and perceived volume are different. My blackface PR was really loud. At the gig we played the other night, your Princeton non reverb tone was great.
     

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