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Thread: reducing reverb effect in deluxe reverb aa763 circuit?

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    reducing reverb effect in deluxe reverb aa763 circuit?

    Built a copy of this circuit and would like to make more of the reverb pot sweep usable. Like most Fender reverbs it goes from subtle to over the top between 2.5 and 3.5/4. Would reducing the value of the 1m resistor at the grid of the driver tube help to hedge against over-verbing, so to speak? Any better ideas?

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    Maybe 12AU7 as the driver?

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    Quote Originally Posted by mozz View Post
    Maybe 12AU7 as the driver?
    Just tried that and it does help some. I may use that as at least part of a final solution... good thinking.

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    Quote Originally Posted by mort View Post
    Built a copy of this circuit and would like to make more of the reverb pot sweep usable. Like most Fender reverbs it goes from subtle to over the top between 2.5 and 3.5/4. Would reducing the value of the 1m resistor at the grid of the driver tube help to hedge against over-verbing, so to speak? Any better ideas?
    One thing I do, is remove the bypass cap on the reverb drive tube's cathode, that'll cut the gain a bunch. And if that's not enough, you can 1) replace reverb return pot which is usually linear, with an audio taper pot and/or B) pad that reverb pot with a resistor in series (at the top of the pot so to speak), I've used resistors from 100K to 1 Meg. Just did a RI twin, used 1 Meg, I get a full turn of the reverb knob and it's still not out-of-hand with it on 10.

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    My preference would be to keep the drive the same and attenuate the output. That way, you keep the noise out of the reverb lower. Simply change the 470K that goes to the reverb level pot to something bigger, try 1M.

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    If you built it exactly to that schematic, change the 4.7M dry signal pad resistor to a 3.3M as used in the AB series of Fenders. That will help balance the dry/reverb better by increasing the dry signal and then you can tweak from there.

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    Too late, I know, but in case anyone else is interested: You can go lower than 3.3M here, to 2.2M. Even th4e AB763s have too much reverb for anything but surf.

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    Quote Originally Posted by mozz View Post
    Maybe 12AU7 as the driver?
    Thatˋs a good idea, I use a TungSol RI 12AU7 as reverb driver V3 in my ˋ67 Deluxe Reverb for a better overall sound in the Vibro Channel and an excellent and subtle reverb tone.
    Zouto

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    Last edited by Zouto; 10-18-2019 at 10:39 AM.

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