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pre-amp causing this ??

Discussion in 'Pickups & Electronics [BG]' started by dougray, Oct 3, 2004.


  1. dougray

    dougray Supporting Member

    Apr 16, 2002
    western maryland
    i have 2 lakland 55-01's,i upgraded the pre-amps to an aguilar obp3's,my amp setup is: sansampRBI-QSC850 ,Hartke 4.5 cab(sometimes i use the hartke 15),i have tryed different strings also,ernie balls,d'addario's and currently i have them both strung with DR lowriders..i play 90% classic rock/80's rock. :bassist:
    ok,here is the problem: the B-E-A strings when playing sound great,its when i play the D and G strings i get a "thin" trebly sound,there is no umph with the D-G strings like i get with the B-E-and A strings..
    i have checked/adjusted my pick-ups,tryed different amp settings,pre-amp settings on the bass,etc.etc.etc. could this be either a string problem?or a pre-amp problem?

    any suggestions? :help:
    thanx... :)
     
  2. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    FWIW:

    The only way I know to troubleshoot is to follow my gut and change one thing at a time and hold everything else constant. Sounds like you've tried enough strings.

    Don't know what pups are in the Lakland but could be the original preamp was designed to work with them and the Aggie just has different tone shaping that doesn't match well - but I doubt it. In general, I've had some pups that tend to get lost like that in either the top end or low end but I don't remember such behavior ever being associated with a specific preamp. Seemed to be more a pup issue that was consistant no matter how the pups were run. That was in using TI Jazz Flats only.

    But if your gut tells you preamp then you could skip the Aggie and wire the pups direct to the jack and run controls off the Sansamp (which I assume probably has some kind of frequency control). Not hard to do and if you get what you want you have your answer - it's somewhere between the pups and jack. If it does the same thing then it's not in the onboard controls and you can look elsewhere.
     
  3. Razor

    Razor

    Sep 22, 2002
    Dallas
    I've experienced the same problem quite a few times.. in all cases it was the pickup(s) that were the dead link. I replace the pickups and adjust their height and problem solved. What kind of pickups are in the Lakland now?
     
  4. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    yeah, I can't think that replacing the preamp would cause that problem.

    If you have the stock Barts in there, then those do typically have a lower output than other passive pickups. The preamp gain trim pot on the bart preamps can be used to adjust for this. With the Aguilar, there's no input gain with eq flat.

    I know you said you've adjusted pickups and tried different amp settings, but you don't say exactly what you did. I'm assuming you've tried different strings etc, and you may have done these already:
    1) Bring your input gain up on your amp.
    2) Pickup height adjustment - the pickups should generally be closer to the G string than the B string to get an even sound across all strings.
     
  5. dougray

    dougray Supporting Member

    Apr 16, 2002
    western maryland
    thanx for replies:
    the laklands have the MK1 barts in there(passive),i am not knocking the sound i am getting,both my basses sound wise is great,its just the D-G strings are "thinner" sounding and treblier<is that a word?...
    i adjusted the pick-ups to the Fender site adjustment specs,the D-G sides of both pickups are higher than the A-E-B side,i set the onboard pre-amp,bass=full,mid=flat(middle detent) treble=full,i have the blend control set at almost middle position(more of the bridge pick-up),my RBI is set at the settings for an ampeg svt4,
    i was reading that going to thicker D-G strings might help,i am going to try that..
    :bassist:
     
  6. luknfur

    luknfur

    Jan 14, 2004
    DIXIE
    FWIW:

    a heavier gauge string should increase the output if nothing else and is why typically the low end of the pup is set further from the strings than the top end to begin with - and usually it works acceptably. I'm guessing a heavier gauge will likely also change tone.

    Barts are typically very well balanced pups. But I've never had MK1's.
     
  7. Fran Diaz

    Fran Diaz

    Mar 28, 2002
    Santander, Spain
    Bassist
    I don't know what are the settings for the SVT in the RBI, but if your setting the bass with full treble and bassand flat mids you are virtually scooping the mids and that can be the problem. Try a flat eq on your bass, you'll have to compensate a little on the input volume of your preamp (RBI) and see (or hear) if the G and D strings are still lost in the mix.

    keep groooovin'
    Fran
     
  8. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    Well, the D and G are always going to be treblier...they are thinner strings. One way to compensate is change your right hand approach, play on the D and G closer to the neck.

    Check your EQ!!!!!

    Boosting the crap out of 40 Hz does nothing to fatten up the D and G strings. The open G fundamental is about 100 Hz and the upper harmonics that make up most of what you hear start at 200 Hz. Cutting out too much mids will suck all the life out of notes you play on the D and G.

    Soapbox time: so many people worry about their amps cranking out 28-50 Hz that they forget that that only matters for the very lowest notes you play. It's the 200Hz-2KHz range that matters for ALL the notes.