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Fender reverb mod both channels

I want to mod my fender normal channel to have reverb I put a jumper from pin 6 on the first pre amp tube to pin 6 on the second preamp tube , that worked but I lost a lot of power on my reverb chanel so I undid it.I tryed the Dan torres method and the amp sqealed it did not like that . Any suggestions?

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  • guitar77 Dec 16, 2007

    It is a fender twin reverb with a master volume. The closest schematic I have found is the fender twin reverb 100 watt rms. It looks really close to the ab763.

  • guitar77 Dec 24, 2007

    I did go to that site the mod was not explained to well and his self drawn up schematic was poor I dont want to fry anything in the amp I just rebuilt it and I'm still just learning thanks

  • guitar77 Dec 24, 2007

    can someone give me a layout or descent drawing of the mod then I think I'll be able to pull it off. I'm still learning and a lot of this is confuseing thank you



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Go to
there is info on this mod. heed the warnings of hot rod activities!!
There is a solution to your misguided nods you mentioned earlier.

Posted on Dec 24, 2007

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This is a pretty simple mod which I have performed 3 times now with great success and even did it last night to my own super reverb. The mod is detailed and well explained in the latest edition of the tube Amp Book by Aspen Pittman of Groove Tubes!

Posted on Dec 05, 2008

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1st step the (2) 220k resistors going to the phase inverter 1 goes to normal channel the other to the reverb vibrato channel diconect the wir going to the normal channel connect that wire to the 3.3m reverb resistor it probably hase a 10pF cap in parellel with it 2nd step now connect the 220k resistor on the leg that you diconected the wire from done you should now have reverb on both channels also made the amp seem a little loader too hope this helps you can contact me at for further info just put reverb help in the subject line so i know. Mike

Posted on Aug 06, 2008

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Posted on Jan 02, 2017

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