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6G2 build Trem noise

Discussion in 'Shock Brother's DIY Amps' started by Mongo Park, Mar 15, 2019.

  1. Mongo Park

    Mongo Park Tele-Afflicted

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    I finished my 6G2 a bit back, glad to see more being built gem of an amp.
    I have read up on the Tremolo noise. Mine makes a wah wah noise with the term oscillation. I keep looking through the forum for something I read about reducing this. Can't for the life of me find it, something about adding a cap somewhere. If somebody knows this could they tell me. I do have a switch to turn it off but the noise is quite prevalent when the trem is in use when the amp is quiet, as in not playing any notes.
    Cheers Ron
     
  2. robrob

    robrob Poster Extraordinaire Ad Free Member

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    Have you tried chopsticking the tremolo wires (to and from the controls and tube)? The tremolo is a powerful signal that can bleed into nearby wires and circuits.
     
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  3. Mongo Park

    Mongo Park Tele-Afflicted

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    No but I will give it a go is it worth using shielded wire.
    Thanks Rob love your site.
     
  4. dan40

    dan40 Friend of Leo's

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    Shielded wire to the grid of the oscillator tube really helped to quiet down the thump in my 6g2 build.
     
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  5. theprofessor

    theprofessor Poster Extraordinaire

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    Here's what I did, on the advice of Jim Nickelson of Lil Dawg (thanks, Jim!):

    (3) 47pF silver mica caps. Two will go in parallel with the two 1M resistors (one on each) on the board that connect the cathode bypass cap and 3.3k resistor to the trem circuit. These go to SPEED potentiometer. One will also go in parallel with the 220k resistor that shares an eyelet with the first .1mF coupling cap. This goes to INTENSITY potentiometer. These will reduce the “heartbeat” sound on the tremolo, which some people dislike.


    Here's one of the pics of my board with the three 47 pF caps circled in red:

    IMG_0493.JPG
     
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  6. Mongo Park

    Mongo Park Tele-Afflicted

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    Great thanks a lot Theprofessor that was what I was thinking my brain had thought. Chopsticks did not fix it, a little shielded wire can't hurt as well. Thanks to all for helping me out with this. My project for the weekend and report back.
    Cheers Ron
     
  7. Mongo Park

    Mongo Park Tele-Afflicted

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    Project is on hold for a few days until proper caps arrive.
    Cheers Ron.
     
  8. jtcnj

    jtcnj Tele-Holic

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    I still need to order those caps though with my trem intensity at zero the heartbeat is very faint.

    the wire to the footswitch trem jack is VERY susceptible to Big motor boat put-put oscillation noise in the vicinity of the output jacks.

    Mine started misbehaving and I knew what it was, sure enough the stranded wire had sagged near the NFB signal feed from the jack.
    The blue and pink leads top left area of picture.

    I may re do the pink trem jack lead a little longer or put a stick-on wire tie base to keep things where they are quiet.

    My filament leads fly over and are not in play.




    start up.jpg
     
    Last edited: Mar 18, 2019
  9. Snfoilhat

    Snfoilhat Tele-Afflicted

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    You're in good hands with the folks helping out on this one!

    There isn't much to add, but I'll chime in this one point: unless you really need your amp's built-in effects to be foot switchable, just omit the the foot switch jacks entirely. Electrically, vintage-style trem and reverb on/off controls are really primitive and asking for noise. Alternatively, install relays like a modern (1980s+?) amp. There's plenty of room in most vintage designs for a little low voltage supply and a couple relays, or at least that's my understanding of it. I just turn my reverb and trem down on the amp's control panel.
     
  10. nasdak

    nasdak Tele-Meister

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    Hi,
    old thread bump but maybe that could help some of you :
    i had a hard time chasing the ticking of a 6G2 trem
    all the usual trick did not work (only the cap across the 220k help a little)
    What did help a lot was to solder a tiny grid stopper (4.7k) just at V1 grid. Even with a shielded wire from te jacks to the grid, it was picking the trem noise from the cathode bypass cap. The grid stopper stop that interference !
     
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  11. jtcnj

    jtcnj Tele-Holic

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    The trem heartbeat always reminds me of Edgar Allen Poe's story "The Tell-Tale Heart".
    Or maybe it is my slightly guilty conscience reminding me to install those snubber caps.....

    "True! --nervous --very, very dreadfully nervous I had been and am; but why will you say that I am mad?"
     
  12. theprofessor

    theprofessor Poster Extraordinaire

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    Wow. I can't un-see that mental image. Now I will always associate the tremolo pulse with someone who has been buried alive. Maybe a dude is in my wall! Arrrrrrrgggghhhhhhh!
     
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  13. jtcnj

    jtcnj Tele-Holic

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    The one you speak of is "A Cask of Amontillado".
    I just went back and read The Tell Tale Heart Again, love it!
     
  14. theprofessor

    theprofessor Poster Extraordinaire

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    Ah, yes! Thanks! Getting my stories confused. It's been too long. Now I've got to pull out my copy of Edgar Allen Poe's complete works and revisit it.
     
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  15. mjcyates

    mjcyates Tele-Meister

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    This is what I did on mine. 47pf caps plus 1n4007 diode across the intensity pot.

    6G2 Main Board.png
     
  16. BigDaddy23

    BigDaddy23 Tele-Holic

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    ^this.

    I'd try the diode by itself first - it worked in mine without the need for the snubbers.
     
  17. Mongo Park

    Mongo Park Tele-Afflicted

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    Thanks for adding on to the thread
    That are a heck of a thing to tame
    So more info will help others when it come their time to quieten the beast
    Cheers Ron
     
  18. Uncle Daddy

    Uncle Daddy Tele-Afflicted

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    Does the diode on the intensity pot fulfil the same function as the diode on the bias board on a regular 6g2 that's not using a bias pot?
     
  19. mjcyates

    mjcyates Tele-Meister

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    Sorry, not smart enough to answer that question. I just took the suggestion from someone else and it seemed to work.
     
  20. dankilling

    dankilling Tele-Afflicted Silver Supporter

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    I have the same issue on my 5f11, so it will be getting opened up soon to add the diode!
     
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