Reverb loud on Princeton Reverb

Discussion in 'Shock Brother's DIY Amps' started by heave1, Oct 16, 2021.

  1. heave1

    heave1 TDPRI Member

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    I built a Princeton Reverb and the reverb is fine up to 2-3 but then gets overly loud. Could it be the wrong pot? Or could I change V1 to a 12AT7 or 12AU7?
     
  2. Wally

    Wally Telefied Ad Free Member

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    V1’s two triodes are the first two gain stages. V2…the 12AT7…is the reverb driver tube. V3 has one triode that is the reverb recovery and one triode that is the third gain stage. So, using a 12AU7 in V2 would decrease the drive signal for the reverb. However, that should not be necessary, ime, to have a good sweep control of the reverb effect. Fwiw, that Reverb control acts on the return signal.
    what potentiometer did you use for that control? Have you experienced BF/SF reverb amps before building this amp?
    It would be of interest to have a voltage chart.
     
    Last edited: Oct 16, 2021
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  3. corliss1

    corliss1 Poster Extraordinaire Platinum Supporter

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    I think this is the critical part here. If you want just a touch of reverb, most Fenders end up on 2-3. Anything more than that and you start surfing, so what you're hearing could be completely normal.
     
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  4. Willie Johnson

    Willie Johnson Tele-Afflicted

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    I do a long plate JJ 12AU7 in my PRRI and like it a lot. 2 is a subtle touch of reverb, 3 is effected-sounding reverb, and 10 is dramatic, Roy Buchanan reverb. Without it, anything above 3 is too washed out and splashy.
     
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  5. Addnine

    Addnine Tele-Holic

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    Fender amps have useful reverb up to about three IME. Beyond that, you're into Boing City, where few dare travel.

    I have come to prefer digital reverb; MUCH more flexible.
     
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  6. Paul G.

    Paul G. Friend of Leo's

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    I don't do this on original amps, but on Fender-style builds I like to add a dwell pot to the circuit.

    Simply replace the 1M grid leak resistor with a 1M pot. I put it in the back panel.

    dwell.jpg
     
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  7. schmee

    schmee Doctor of Teleocity Silver Supporter

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    You can use a mod that replaces the pot and adds a resistor to change the reverb so you have the stock 0-5 spread out over 0-10. Gives you finer control too. Most Fender amps 0-5 is more than adequate to me.
     
  8. Lowerleftcoast

    Lowerleftcoast Friend of Leo's

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    Not sure of what you are looking for.

    An audio taper pot will bring the effect on a bit higher on the dial.

    A smaller cap (.0022uF) replacing the .003uF will reduce more of the lower frequencies of the reverb signal.
     
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