Vintage Mu-Tron III

Discussion in 'The Stomp Box' started by Kozmo, Jul 2, 2019.

  1. Kozmo

    Kozmo TDPRI Member

    Age:
    53
    Posts:
    20
    Joined:
    Jun 10, 2019
    Location:
    Upper left USA
    I just acquired one of these in a package deal. Unfortunately it's not working properly.
    I know there are folks I can send it to for an overhaul but I thought I'd ask here first.

    So it "wahs" when engaged, like a wah pedal rocking back and forth, but it doesn't "auto-wah"- it doesn't react to individual notes or pick attack, no matter where I set it.

    Any Mu-Tron experts in the house?
    IMG_4493.jpg
     
    zippofan and BorderRadio like this.
  2. Utah Joe

    Utah Joe Tele-Meister

    Posts:
    111
    Joined:
    Jun 2, 2015
    Location:
    Golden Valley, MN
    Try this: http://www.lsound.com/
     
  3. Kozmo

    Kozmo TDPRI Member

    Age:
    53
    Posts:
    20
    Joined:
    Jun 10, 2019
    Location:
    Upper left USA
    Thanks, Utah Joe.
    Yes, that's probably the best guy to send it to. But that'll cost me another $200. I'm not sure it's worth it.
     
  4. dan1952

    dan1952 Friend of Leo's

    Age:
    67
    Posts:
    4,523
    Joined:
    Jun 24, 2004
    Location:
    Anderson, IN
    If you get it fixed it won't be original. Oh no!
     
  5. brokenbones

    brokenbones Tele-Holic

    Posts:
    596
    Joined:
    Mar 15, 2012
    Location:
    Indy
    Have you opened it up and given it a visual inspection?
     
  6. Kozmo

    Kozmo TDPRI Member

    Age:
    53
    Posts:
    20
    Joined:
    Jun 10, 2019
    Location:
    Upper left USA
    Yes, looks clean inside- no burnt components. No loose wires.
     
  7. zippofan

    zippofan Tele-Afflicted

    Posts:
    1,330
    Joined:
    Mar 16, 2014
    Location:
    Pennsylvania
    A schematic is available over on the Madbean site, I just completed a clone circuit and it sounds terrific. Look for the "Naughty Fish" build and forum threads. There is also one on General Guitar Gadgets but it's a variant.
    mutron_complete.jpg

    The Sweep circuit includes the Vactrols (LED/LDR) which in the original were custom made parts. The Madbean clone uses an Xvive part that mimics the original but isn't exact. Madbean's build doc would be a good place to start troubleshooting. I think you could find the original schematic on the web too.
     
    Kozmo likes this.
  8. Kozmo

    Kozmo TDPRI Member

    Age:
    53
    Posts:
    20
    Joined:
    Jun 10, 2019
    Location:
    Upper left USA
    Awesome. Thanks zippofan!
     
    zippofan likes this.
  9. zippofan

    zippofan Tele-Afflicted

    Posts:
    1,330
    Joined:
    Mar 16, 2014
    Location:
    Pennsylvania
    Good luck, I hope you are able to get it working again! It's an awesome effect, I really love it, from subtle to over the top it sounds great.
     
  10. sirbergersworth

    sirbergersworth Tele-Holic

    Posts:
    560
    Joined:
    Aug 30, 2011
    Location:
    St. Louis, MO
    I didn’t know this circuit was capable of an “auto wah” type of sound. I thought it was only an envelope filter. Have I been wrong all these years.
    I wonder if a cap is out of spec and the thing is self oscillating.


    Sent from my iPhone using Tapatalk
     
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.