Aguilar Tone Hammer Internal Trim Pot?

Discussion in 'Amps and Cabs [BG]' started by PolkaHero, Jan 2, 2017.

  1. PolkaHero


    Jan 5, 2002
    I just took apart my Aguilar TH350 amp for its annual cleaning where I blow it out with compressed air and clean all the pots and jacks with DeOxit. I noticed what looks like an internal variable resistor on the preamp circuit board, see attached pic. Is this some kind of a trim pot and if so what does it control?
  2. BassmanPaul

    BassmanPaul Inactive

    Is the amp working as it should? If so leave it alone and don’t try to fix what ain’t bust! :)

    Be very careful with compressed air. If used carelessly you can blow stuff right off the board.
    aprod and CharlieC like this.
  3. PolkaHero


    Jan 5, 2002
    Works great, just curious.
  4. BassmanPaul

    BassmanPaul Inactive

    You know what curiosity did don’t you? :D
  5. Andyman001

    Andyman001 moderation must be taken with a grain of salt

    Feb 11, 2010
    S/E Idaho
    lancimouspitt likes this.
  6. kpc


    Apr 6, 2011
    I wouldn't open any amp unless it's needed. Those amps are the best. I know, I have one. If it doesn't shut off, don't open it.....
    rodl2005 likes this.
  7. PolkaHero


    Jan 5, 2002
    It's no longer under warranty. You mean none of you guys take apart your computers and other electronic equipment and blow the dust out at least once a year? I don't bother with my amps that have dust covers but this one sits out in the open most of the time. You would be surprised how much dust accumulates inside!
  8. Jaco who?

    Jaco who?

    May 20, 2008
    I'd contact Aguilar and ask. You'd hope it's something interesting, like a mid frequency Q adjustment, but more likely it's something boring like making sure the input gain is consistent for each unit that goes out the door. I'm curious too.
  9. PolkaHero


    Jan 5, 2002
    I can't find a schematic online nor do they provide one in the manual. I bet they won't tell me what it's for but I can try asking!
  10. beans-on-toast


    Aug 7, 2008
    I don't have the schematic. Maybe the pot is for setting a bias.
    Last edited: Jan 2, 2017
    metalinthenight likes this.
  11. 'til the experts comes along with the difinitive answer, my WAG is that it's some kind of a bias pot.
    Or it may be used to set the amp's overload protection trip point.
    In any case, it's not there to dink with.
    "No user serviceable parts inside." Ya know?
    If they wanted you to turn it they would have put a knob on it and stuck it through the front panel.
    But nice that you gently clean the innards regularly.
  12. Jeff Scott

    Jeff Scott Rickenbacker guru..........

    Apr 11, 2006
    Out there!
    It got me into some "places" ;) drool I probably would not have gotten into without the curiosity. ;) :D :) drool :hyper: :bassist: :D ;)

    That pot is on the preamp board. Probably not power amp bias related (how are Class D amps biased, anyway?).
    agedhorse likes this.
  13. BassmanPaul

    BassmanPaul Inactive

    I do clean the cooling paths of my amplifiers but do it with a vacuum and wearing a face mask. The fans in the amps can suck up all sorts of crud some of which will not be good for you. Blowing it out puts all that stuff back into the air to be taken in by your lungs.
    S-Bigbottom likes this.
  14. Fergie Fulton

    Fergie Fulton

    Nov 22, 2008
    Retrovibe Artist rota

    So what did the cat want to know????
  15. beans-on-toast


    Aug 7, 2008
    Last edited: Jan 2, 2017
    HolmeBass likes this.
  16. Jeff Scott

    Jeff Scott Rickenbacker guru..........

    Apr 11, 2006
    Out there!
    Yeah, without having seen one opened up (or, own one) given how tight that photo, above, this should help.

    Aguilar TH500-jastacey128a.jpg
    Last edited: Jan 2, 2017
    beans-on-toast likes this.
  17. NoiseNinja

    NoiseNinja Experimental-psychedelic-ambient-noise-drone Inactive

    Feb 23, 2011
    Yes, curiosity pretty much gave birth to all great inventions and discoveries, including music in all it's forms.
  18. two fingers

    two fingers Opinionated blowhard. But not mad about it. Inactive

    Feb 7, 2005
    Eastern NC USA
    1) Have a few beers.
    2) Turn on amp and start playing.
    3) Hand the screwdriver to a buddy....preferably one who has also had a few.
    4) Tell him to turn that sucker back and forth so we can all find out what it does.
    5) Ignore 1-4..... and that trim pot.

  19. beans-on-toast


    Aug 7, 2008
    Perspective helps but, without a schematic, the function is about as clear as mud. :laugh:
    Jeff Scott likes this.