Dismiss Notice

Psst... Ready to join TalkBass and start posting, make new friends, sell your gear, and more?  Register your free account in 30 seconds.

Active Volume Louder Than Passive- Is It All In The Preamp?

Discussion in 'Pickups & Electronics [BG]' started by Bryan R. Tyler, Jun 1, 2005.


  1. Bryan R. Tyler

    Bryan R. Tyler TalkBass: Usurping My Practice Time Since 2002 Staff Member Administrator Gold Supporting Member

    May 3, 2002
    Connecticut
    My fretless Elrick with a Bart 3-band has a noticeable difference in volume when switching between active and passive (with no EQing). I'm used to this- it's been like this on my other active basses I've had in the past, IIRC.

    But my fretted Elrick with an Aguilar OBP-3 has the same volume when switching between active and passive. The volume only boosts when the EQ is put into use. I REALLY like this. Is the preamp alone responsible for the difference in active/passive volume (both basses have pretty much the same Bart soapbar pickups)? Is there a way to adjust it so the active volume is about the same as the passive?
     
  2. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    In this case, it's the difference between bart and aguilar preamps.

    Your bart 3 band preamp has a gain trim control (it's a little blue trim pot, usually on top of the main bart unit but I've seen it as a separate item). The Aguilar preamp has no such gain, and so the passive sound sounds the same as active with no eq to my ears.

    You can adjust the gain on the bart trimpot so that active with no eq should sound same as passive.
     
  3. Bryan R. Tyler

    Bryan R. Tyler TalkBass: Usurping My Practice Time Since 2002 Staff Member Administrator Gold Supporting Member

    May 3, 2002
    Connecticut
    Thanks for the response, David. I can't seem to locate the trim pot- can you see it in either of these pics? I can take more, or bigger, ones if that helps.
    [​IMG]
     
  4. Bryan R. Tyler

    Bryan R. Tyler TalkBass: Usurping My Practice Time Since 2002 Staff Member Administrator Gold Supporting Member

    May 3, 2002
    Connecticut
  5. Trevorus

    Trevorus

    Oct 18, 2002
    Urbana, IL
    wouldn't it be that little yellow pot on the green/grey/blue wires? Or would that be some sort of frequency select?
     
  6. Bryan R. Tyler

    Bryan R. Tyler TalkBass: Usurping My Practice Time Since 2002 Staff Member Administrator Gold Supporting Member

    May 3, 2002
    Connecticut
    You're right-that's it. I just adjusted it was was going to post that I found it-I was looking for something blue and just passed it by at first :meh: :p
     
  7. Bryan R. Tyler

    Bryan R. Tyler TalkBass: Usurping My Practice Time Since 2002 Staff Member Administrator Gold Supporting Member

    May 3, 2002
    Connecticut
    What a world of difference!! Okay, please forgive me- I've been playing for ten years now, and still know zilch about wiring. I just adjusted it down to the same volume as the passive- it turns out the gain was all the way up.

    Now the whole bass works better! There used to be a drastic difference between setting the pickup blend in the center and turning it either towards the bridge or the neck- it didn't have a smooth transition like it does now. Also, I used to have to turn the Blend knob on my Sansamp RBI pre down because the output was so hot from the fretless it would cause an overdrive/distortion type sound, and now I don't have to. Thanks a lot guys!
     
  8. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    yup, you found it. When I've seen it on the main unit, it's generally been a blue trimpot. Glad to be of help