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5 string preamp in 4 string bass?

Discussion in 'Pickups & Electronics [BG]' started by luknfur, Feb 8, 2004.


  1. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    Anybody know any reason a 5 string preamp would not work in a 4 string bass if the pups output is within parameters of the preamp?
     
  2. Nino Valenti

    Nino Valenti Commercial User

    Feb 2, 2001
    Staten Island NYC
    Builder: Valenti Basses
    There is no reason that it would not work.
     
  3. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    That's what I thought. Stuck in a Bart XTCT-LZ harness out of a '97 Tobias Classic 5 and get distortion in the active mode, not passive. Checked all connections, grounds with no change. Supposed to work with medium range output pups and I've got Bart M34C's which according to my meter are around 45 mV.
     
  4. Halftooth

    Halftooth Supporting Member

    Nov 24, 2002
    Tri-Valley, NorCal
    There's no reason it shouldn't work! The eq points will be different though, as I would assume that the low end frequency would be set at a lower point to help boost the low B. Even that should be a very minor issue though in terms of sound.
     
  5. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    I had an NTMB in the bass before with no problem but the sound was just too dark so I tossed in the XTCT-LZ. Sound seems to have potential but get distortion at some "hotspots" when using medium to strong attacks, depending on the note, some notes don't distort (mostly between the 3rd and 12th frets). I get the impression there's just too much gain but no trim pots were in the harness. It does have DTA1.3 buffer. The 25K volume pot is supposed to lower the output to 1.25 volts but you're supposed to use a 250K volume with an active/passive switch. I've done both and you can't tell the difference and distortion remained.

    The unit was reportedly in good working condition and I see nothing that would indicate otherwise with the exception of epoxy on the preamp, mid, and buffer units - so these units had to be busted loose to remove them. And that is some tough stuff and can require some force when proper technique is lacking.

    The harness was intact when it arrived except the mid unit (Gibson not Bart MCT), had two wires free (3 wire unit, instead of the 2 wire bart). But I'm fairly certain I've figured the wiring out cause the mid unit gave plenty of boost and removing it totally eliminated boost but distortion remained as before.

    I've pulled the XTCT harness and going to throw in a TCT harness I
    have that I haven't tried in this bass. Tired of the bass being of little use.

    But I just wanted some feedback as to whether my assumption that the XTCT unit should work was sound, and for future reference.
     
  6. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    yes, your assumption was correct.

    Do you have active pickups also? Running active pickups and preamp on 9v can give you little headroom and cause the distortion you mention. Why not try it at 18v?
     
  7. luknfur

    luknfur

    Jan 14, 2004
    DIXIE

    Bart M34C's, passive. But actually, it never occured to me the distortion may be due to being underpowered, aside from initially making sure the 9v was up to snuff, but it is a 9v harness. The distortion in terms of sound was actually somewhat similar in sound to low battery but it wasn't an across the board distortion like when a batteries down. But it's a thought.
     
  8. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    Well the Schec is back an the active list, TCT implant with no problem. But between the NTMB, TCT, and XTCT-LZ, I think the XTCT-LZ was the best in tones (the distortion who knows?). One things for sure, it's not the Gibson mid unit that was the culprit. I used it for the mid with the TCT. Maybe I'll figure it out or accidentally get it right next implant. And it could be the NTMB was too dark because of the 50K tone pots. I've really never noticed any difference in tone pots but 50K is getting pretty minimal. The TCT works fine but is a bit heavy with the Bart tone. I have a bass with PJ Barts with an NTCT preamp and it's not so thick with it. But it may be those M34C's I'm not too fond of, or that Gibson mid unit for that matter.

    Regardless, if any one has any further thoughts about the distortion thing, lay it out. Cause it will go back in something as soon as I feel like messing with it again or feel I may have it resolved, or maybe when I latch onto another Bart mid unit. Is it any wonder lots of players prefer passive.