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Hoffman Amps Forum image Author Topic: Alternate reverb switching scheme for AB763: grounding the driver  (Read 1793 times)

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Offline Hoodnight

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On an AB763 style footswitched reverb, given the sensitivity of the reverb recovery stage does it make more sense to instead use the footswitch to ground the grid of the preceding reverb driver stage in V3? This allows for the most direct path from the reverb return jack to the grid of V4A.

The noise from the reverb recovery stage would be constant rather than switched, but you'd also get reverb trails continuing after switching the reverb off.


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Offline pdf64

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Re: Alternate reverb switching scheme for AB763: grounding the driver
« Reply #1 on: November 21, 2022, 06:43:09 am »
Interesting idea, but doing that will put a low pass filter on the dry signal path.
I suppose there’s ways around that, eg putting the switch after an added grid stopper.
To reduce noise, I suggest to consider the switching arrangement of the DRRI, ie at the input to the reverb control https://el34world.com/charts/Schematics/files/Fender/Fender_65_deluxe_reverb_reissue_sm.pdf
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Offline PRR

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Re: Alternate reverb switching scheme for AB763: grounding the driver
« Reply #2 on: November 21, 2022, 12:46:07 pm »
Use a switch. Try both ways.

I can see pre-kill for when reverb trails are a thing, and post-kill when dead-silent pause is wanted. Neither may be an everyday desire, but both could come up in one show.

 


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