Bart preamp problems

Discussion in 'Luthier's Corner' started by Fasoldt Basses, May 3, 2005.

  1. Fasoldt Basses

    Fasoldt Basses

    Mar 22, 2005
    Stevens Point, WI
    Karl Thompson, Builder (Formerly Fat Karl)
    Well, this weekend I finished building my 5 string ( 3rd instrument I've built- pics will be up ASAP) and installed a bartolini preamp from
    Everything works fine and sounds phenominal (sp), except the volume control: There is no sound until the knob is turned almost all the way up, i.e. only the last 10 or 15% of the control is letting the signal through.
    Perhaps there is an easy explaination to this that I'm just spacing out - any help here would be greatly appreciated.
  2. did you get a harness or did you put your own pots? active preamps generally use different pot values than passive electronics.

    Also, don't you know you are REQUIRED to post pics of your finished instruments before anybody helps you around here? ;)
  3. Fasoldt Basses

    Fasoldt Basses

    Mar 22, 2005
    Stevens Point, WI
    Karl Thompson, Builder (Formerly Fat Karl)
    Thread started.

    The preamp was a harness. The volume control is just a normal 250K audio-taper pot with a push/pull switch.
  4. Scott French

    Scott French Dude Supporting Member

    May 12, 2004
    Grass Valley, CA
    The only Bartolini stuff I've bought has come with pots but I am pretty sure they should be 50k linear.
  5. FBB Custom

    FBB Custom TalkBass Pro Commercial User

    Jan 26, 2002
    Owner: FBB Bass Works
    The EQ pots are 50k linear, the volume should be a 250k audio for most passive pickups.
  6. Wademeister63


    Aug 30, 2004
    Denton Tx
    That is very strange!

    My bass bass also has a prewired Bart preamp from Bestbassgear (NTBT) and it has a similar problem. When I turn the volume up to only about one quarter, it's at full volume already. I don't really have much adjustment at all, pretty much an on/off knob as it is. I've also tried substituting different pots and adjusting the gain trimpot, but haven't been able to cure the problem. I've also double checked my solder joints looking for problems, bad grounds or whatever but haven't been able to find the problem or fix it. I did have one of the original solder joints come loose while I was installing everything, but I resoldered that. Maybe there is another solder joint that's barely connected but I don't want to rip everything apart to find it at this point.
  7. Luke Sheridan

    Luke Sheridan Commercial User

    Dec 30, 2004
    Yonkers, NY
    I build guitars and sell them. Strings, too
    The last time I checked, BestbassGear said they solder the push-pull volume pots as an option. (At least on the HR4.6 for the Active/passive mode) So It's not coming from Bartolini set up like that.
  8. bestbassgear


    Aug 2, 2003
    Sorry to hear about the problems with these Volume pots with the Bart Preamps. These are sold to me as pre-wired harnesses, we actually only wire up the Aguilars....

    I have a couple spare pots that I can send to you if you want to replace the pots.

  9. Wademeister63


    Aug 30, 2004
    Denton Tx
    Brian, that is extremely cool for you to notice this and make the offer. I guess if I had thought it was your fault or problem I would have contacted you about it. Instead, I just kind of gave up after trying a few things and used that knob as an of off switch. Maybe the pot really is bad and a new one would change my feelings of frustration at this bass.
  10. Fasoldt Basses

    Fasoldt Basses

    Mar 22, 2005
    Stevens Point, WI
    Karl Thompson, Builder (Formerly Fat Karl)
    Yes, Thank you so much! Hopefully this will solve the problem. :)
  11. luknfur


    Jan 14, 2004

    first I'd go to in installations and find the closest thing to what you've got. If a linear pot was stuck in for volume instead of an audio you could get wierd respons. You can check the volume pot with a meter (with an arm) and see if it moves smooth or jumps suddenly. If it jumps suddenly pots probably junk. There's just a thin path of carbon (I think it is) that the wiper trails across and if it doesn't make contact or the carbon's trashed - then there's a problem.

    I've had lots of pre's and pots, and tortured them to death learning and never had a problem with a pot - except one the stem was pull out from a press-on knob (which know reside in drawers, not on basses).