Any cases of compressor pedals destroying pre amps?

Discussion in 'Effects [BG]' started by gmasca92, Dec 4, 2012.

  1. gmasca92


    Apr 9, 2012
    I think this happened to me. I was using a keeley compressor (4 knobs) with a bass that had an obp-1 (aguilar) and the pre amp was destroyed.

    Is this normal or just coincidence?
  2. smperry

    smperry Moderator Staff Member Gold Supporting Member

    Nov 3, 2003
    Bay Area, CA
    Endorsing Artist: Martin Keith Guitars
    Moved., your compressor did not destroy your preamp. The only way it could is if you opened up the control cavity of your bass and hit your pre with your pedal.
  3. kreider204


    Nov 29, 2008
    WI, USA
    Oh, THAT'S what I've been doing wrong ...

  4. Oracle

    Oracle Banned

    Sep 7, 2012
  5. petrus61

    petrus61 Supporting Member

    Could you be a little more vague next time?
  6. SirMjac28

    SirMjac28 Patiently Waiting For The Next British Invasion

    Aug 25, 2010
    The Great Midwest
  7. It's possible to burn up a amp input with a pedal, but you're going to need some massive gain to do it. A single pedal won't do it. You'd have to have multiple gain stage pedals (any pedal with an output volume control on it) turned wide open. And then it would have to be long term. The feedback would be insane.

    If you have a tube preamp did you check the tube?
  8. boomertech

    boomertech Frank Appleton Supporting Member Commercial User

    Apr 8, 2009
    Syracuse, NY
    Designer/Owner of FEA Labs
    The preamp will only see the output voltage of the last pedal connected to it, regardless of how many are on your board.

    Most pedals operate on 9Vdc. The worst case scenario would be if the pedal seriously failed and sent all of its power supply to the input of the preamp. Even in this scenario, the preamp usually has over voltage protection circuits at the input and it will survive just fine.

    EDIT: OK… I just reread the OP’s question and he is asking about the pre on his bass. The only way I can see the preamp remotely being damaged is if he connected the bass to the output of the compressor. Even then the circuits should be protected for this.

  9. bongomania

    bongomania Gold Supporting Member Commercial User

    Oct 17, 2005
    PDX, OR
    owner, OVNIFX and OVNILabs
    I suppose if there was a major power spike in the neighborhood, and if coincidentally there was a bad ground in the chain, and no ground at the wall, it would be possible for the power surge to travel back up the guitar cable. The path of least resistance would head toward the player (as "ground"), via the strings, bridge, preamp ground, burning up the preamp along the way.

    Of course this is incredibly unlikely, and has nothing to do with compressors per se.