Adding Reverb

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by guiltless, Aug 15, 2008.

  1. guiltless

    guiltless Member

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    Does anyone know of a good schematic or layout for adding reverb to an amp that doesn't have one? I don't mean the kind that are add on units that attach to the side of your amp, but an actual point to point wired unit that goes inside the chassis. Specifically inside my peavey classic 30 chassis that I am gutting and building a Lightning clone into. I know both sides of each 12ax7 are being used on the Lightning, but I will already have an extra hole that I would be plating off to add another one and can cut a hole for a second if need be... I am just not sure what I need exactly.

    I can read and understand a schematic, but right now reverse engineering the solution from an amp that has reverb is just out of my ability at the moment.

    Thanks!
     
  2. guiltless

    guiltless Member

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    ha ha... thanks. I have search "add reverb" "add reverb matchless" and tons of others, but "add reverb amp" came up with more than any of them.
     
  3. mageerc

    mageerc Member

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  4. guiltless

    guiltless Member

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  5. WaltC

    WaltC Member

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    I added (as an experiment) a minimal reverb to a EL-84 based 5E3 Deluxe circuit I built using a fender-style reverb transformer and compatible tank using just one side of a 12AX7 as the driver and the other side as recovery. It worked and sounded good but was way less reverb than is usual in classic Fenders. I think that for all but surf and like music it's got adequate reverb to enhance the sound stage and provide the added depth that most folks use most of the time.

    Worked, wasn't to tough to do, and functioned well. Might be worth a try...
     
  6. donnyjaguar

    donnyjaguar Member

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    My DSP pedal has more reverb than the wettest surf guitar twang. If your amplifier was something superior to the Peavey I'd be on your side, but in this case the solid state technology wins out in my view. Not trying to poo on your rig, but just feel time/effort/cost vs reward aren't where they need to be to justify this exercise.
     
  7. RedRock

    RedRock Member

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  8. OlAndrew

    OlAndrew Member

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    Might wanna think of something like my Guild....tank drives off the speaker through a power resistor and a cap, and there's a seperate little amp driving a second speaker as the wet output.

    Instead of going all the way to a power tube on the second amp, just blend/feed it's output to grid on the 2nd existing preamp. Using both sides of single 12ax7, or maybe a 12at7, which you say you have room for, might work just great.

    THe first Kevin O'Conner book, in the Ultimate Tone series details lots of reverb circuits. There's a circuit like what I'm describing in there. He's got stuff on doing the mix/blend too. Worth looking into.
     
    Last edited: Aug 15, 2008
  9. guiltless

    guiltless Member

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    I am pretty sure in my OP I said that I was going to be gutting the Peavey guts and building a Matchless Lightning into it.

    The Classic 30 has reverb already there, but it's all in the crappy Classic 30 circuitry so it's getting ditched with the rest of the internals.

    This amp is being done because I need something small and portable to play at churches and clubs. The Bassman with the 4x10 Marshall cab is a bit much for those applications.
     
  10. guiltless

    guiltless Member

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    Thanks for the suggestion on the read! I am always into learning more wherever I can!
     
  11. guiltless

    guiltless Member

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    Hmmm... That gives me something to think about. With all of my planning I didn't consider how easy or not it might be to get in there to work.

    My budget is pretty tight and I want to make sure I am getting quality components so I thought i'd save some money by building it into the Classic 30.
    Maybe I should just sell the Classic 30 and the Marshall 4x10 and invest in a good open back 1x12 and make the Lightning into a head instead.
     
  12. tommytomcat

    tommytomcat Member

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    There are examples of one tube/12ax7 reverb circuits on the hoffman site. http://www.hoffmanamps.com . Just go to the amp forum and do some searches. There's also a user schematic section there as well that has several examples. You'll need 1 extra tube and room for 4-5 extra components.
     
  13. phsyconoodler

    phsyconoodler Member

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    Why not just build a nice Lightning and use a Holy Grail reverb unit in front?
     
  14. guiltless

    guiltless Member

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    Well, a little old lady just totalled my car so this project is on the back burner while I get another car. I think to satisfy my needs for something small I may just try to sell/trade my Marshall 4x10 and scale down to a 1x12, 2x10 or 2x12.
     

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