NAD: '77 Silver-face Vibro Champ

Discussion in 'Amp Central Station' started by GoodwillHunter, Oct 23, 2021.

  1. GoodwillHunter

    GoodwillHunter Tele-Meister

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    Got my first real tube amp a couple of weeks ago (I'm a millenial that grew up on amp modeling).

    This '77 vibro champ appears to be completely original, including Fender special design tubes and speaker.

    Took it apart today to clean and tighten up the pots and tube pins and take some pictures.

    Sounds really amazing! Clean up to 5 then starts to crunch. Thought about re-capping just given its age, but I probably will just play it until it dies because it sounds sweet as is.

    One mod I want to add is the tone-stack bypass. Tried unhooking the 15k resistor from the Bass pot to ground, and holy crap it makes it a great distortion amp and way louder! Thinking about removing the RCA jack for the vibrato footswitch and installing a 1/4" TRS switching jack so I can use a double amp footswitch to engage vibrato and turn on the "RAW" bypassed mode. Has anyone tried that?
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  2. Crobbins

    Crobbins Friend of Leo's Silver Supporter

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    Nice score, congrats.
     
  3. archetype

    archetype Fiend of Leo's Ad Free Member

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    Cool! Go ahead and give it a cap job. Do it to keep other components safe and because right now it might not sound as good as it will with healthy caps. Those are 44 years old and have been consuming themselves on the inside.
     
  4. Ringo

    Ringo Poster Extraordinaire

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    I did that mod with a push pull pot years ago, it was pretty cool, very loud raw tweed sound. I'm sure you can find mod info online on how to do it, I may still have the info somewhere.

    I bought a super clean SF Champ many years ago for $35, should have never sold that one, they go for stupid money these days.
    Congrats on your "new" amp, you will enjoy it.
     
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  5. teleman1

    teleman1 Friend of Leo's

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    I think the mod you are speaking of is the negative feedback loop;common mod.
     
  6. teleman1

    teleman1 Friend of Leo's

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    tubes? probably RCA.
     
  7. RadioFM74

    RadioFM74 Friend of Leo's

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    Cool!

    I second @archetype : if I understood things correctly, you should leave the signal caps alone but change the electrolytic caps… should not sound any less good and it will keep your amp healthy for longer.
     
  8. Intubator

    Intubator Tele-Holic

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    Third on just the filter caps. I like F&T's, have served me well and reliable in vintage amps.
     
  9. Fiesta Red

    Fiesta Red Poster Extraordinaire

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    Very cool…congratulations!
     
  10. archetype

    archetype Fiend of Leo's Ad Free Member

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    If a signal cap is bad it needs to be replaced, though.
     
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  11. SnidelyWhiplash

    SnidelyWhiplash Friend of Leo's

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    Fantastic amp! Put a lil luv & care into it & it should last you quite a long while.

    OP, just love your screen name. I'm a GW fanatic! :)
     
  12. RadioFM74

    RadioFM74 Friend of Leo's

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    Indeed: all should be checked. Not automatically replaced though as is the case for very old electrolytics. That's what I meant ;D
     
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