help with reverb on both channals for fender amps!!

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by frankiestarr, Jul 19, 2008.

  1. frankiestarr

    frankiestarr Supporting Member

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    Hi everyone....

    I have had quite a few fenders modded to have reverb on both channals over the years with good results...Got the info from a popular amp tech/book, his name esapes me at the moment.....I think it was jumpered from the second pre-amp tube somehow....
    Anyway, I had a new circuit board twin and new deluxe modded and the tone of the reverb sounded alot darker.....I didn't recall this happening on my older fenders....The tech said it was because it had more resistance in the reverb circuit now....
    Can anyone shed some light on this? Is it commen when doing this mod for the reverb sound to change? Is there a way to make it sound like it did stock, but on both channels???

    Thanks
    Frankie
     
  2. mbratch

    mbratch Member

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    You'd have to look at the schematics of those amps. I'm not sure what models exactly you're referring to. Even the vintage Fender amps had a slight difference in signal path (there's a coupling cap that's different between normal and vibrato channels).

    But for the reverb sound on the previous reverb channel to change after the mod, then that's based upon how the mod was done. Technically, yes it's possible to make the reverb sound different after the mod. But in that case, maybe the mod wasn't done correctly. Unless you show what was modified, there's no way to really answer the question.
     
  3. frankiestarr

    frankiestarr Supporting Member

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    Ok Thanks for the quick response.....Here are the instructions I gave my tech from Kevin O'Connor.....
    Lift one end of the 220k mix resistor for the normal channel, then add a wire from the plate of the second stage of one channal to the plate of the second stage of the other channel, the wire can be added socket to socket....Hope this helps! Please help/advise if you can....

    Thanks
    Frank Bobey:JAM
     
  4. mbratch

    mbratch Member

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    What model of Fender amps are you referring to?

    If your tech hasn't worked no this kind of amp before and doesn't know how to make the change without instructions, then the instructions you gave (if that's exactly what you told him) are probably pretty vague and can be misinterpreted. The best way to do it is to have a schematic or layout showing the change with a mark-up.
     
  5. frankiestarr

    frankiestarr Supporting Member

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    They are a Fender Twin Reverb Re-Isuue....and a 65 Deluxe Re-issue.....I'll see if I can find out more details....thanks for the help....
     
  6. WaltC

    WaltC Member

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    On the BlackFace and SilverFace fenders the mod's not too difficult, but on the re-issues w/ their pc-boards and microscopic components (yes, I'm old) I wouldn't want to mess with it. I'm sure Kevin O'Connor wasn't talking about doing the mod on the re-issues FWIW. I'm not even sure (current Fender Techs?) that the re-issues do the reverb circuit the same, but probably since they have the tubes and the reverb tranny....
     

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