Onboard pre with true bypass??

Discussion in 'Pickups & Electronics [BG]' started by raal, Jun 24, 2008.

  1. raal

    raal Supporting Member

    Feb 5, 2008
    Minneapolis / St Paul
    Since I had the barts in my '01 535 Rbass replaced with Nordstrand NJ5's, I have grown weary with the sound of the Bartolini HR 5.4 preamp to the point that I end up using the bass in passive mode all the time.

    To me, the frequency boost is just way overboard for this kind of sensitive pickup. Also there is a certain coloration as soon as the preamp is engaged, even when set flat.

    I guess this is nothing new to most of you TB'ers ;)
    I read some interesting posts about the Glockenklang pre. I was close to buying one, until I got confirmation from Glockenklang that the passive / active switch is not a true bypass. However the sound is supposed to be "close" to the passive wired bass.

    Does anybody out there know about preamp that is a true bypass in passive mode?

    Thank you

    For explaination, like in pedals, it is a true bypass when switched passive, the signal goes directly from the pickups to the output jack. Just as if the bass was wired passive ...
  2. basadam


    Nov 29, 2005
    To my knowledge Sadowsky is a "true-bypass" preamp.

    As a matter of fact any on-board preamp can be made true-bypass. The trick is to blend the pickups "before" the circuit.
  3. Hollow Man

    Hollow Man Supporting Member

    Apr 28, 2003
    Springfield, VA
    The Sadowsky should be. Aguilar preamps also can be.
  4. Shiveringbass


    Aug 21, 2005
    Hey there,

    I don't know if Glock is true bypass or not but it absolutly rules.

    In fact, with some pre like Carvin pre or Warwick one with a active passive option, I would usualy not care about passive. But on the Glock, thanks to the passive tone function, I found some very usable tone that I could not get in active for instence bridge pickups with tone rolled all the way off for that Jaco thing.

    Sincerely, I think you should not forget glock pre just because it is not true-bypass.
  5. JackANSI


    Sep 12, 2006
    yes any pre can be true bypass with the right switch wired in. I do it all the time.

    but it almost sounds like you would probably be happier with no pre and just a passive setup. No one needs a preamp, its all a matter of taste. If you like what your pickups are doing alone, then you're done, you found your tone.
  6. UdoGlockenklang


    Aug 23, 2006
    Hi raal,
    the active/passive switch at our onboard preamp is a real bypass switch.
    punchdrunk likes this.
  7. maurilio

    maurilio Guest

    May 25, 2003
    If you like the Nordstrand pups, why not a Nordstrand preamp?

    Call the shop...

  8. raal

    raal Supporting Member

    Feb 5, 2008
    Minneapolis / St Paul
    The same question was asked directly to Salwender who represents GKL in in the US. I got a kind explaination that because the p/u are wired through the preamp circuit, a true bypass is not achievable. However the circuit, being natural sounding, would sound comparable to a true bypass.

    In the first post of this thread, a description of true bypass was given. Maybe everyone has a different interpretation of true bypass.
  9. raal

    raal Supporting Member

    Feb 5, 2008
    Minneapolis / St Paul
    Any link to schematics info?
  10. 4Mal

    4Mal Gold Supporting Member

    Jun 2, 2002
    Columbia River Gorge
    I had Dave Meadows wire my first 3ZB with an Active Passive switch. Both pickups straight to the Jack. It would have been a simple enough thing to wiring in a separate tone control for them. What I found was that I never used that setting. The Audere is so uncolored when set flat that it was just unnecessary for my uses. I had him rework that particular pre later and had him remove that switch.

    One thing you might want to try is wiring both pickups to the jack and listening to it that way - you're going to get a big volume boost and a lot of hi end. You'll need to compensate at the amp to adjust for the gain boost to make an honest evaluation of the tone. You might find yourself re-thinking the idea that true bypass is necessary.

    FWIW - I have the stock Bart MK1 electronics in a Lakland 55-01 with Nordstrand Big Singles. That pre is coming out shortly.
  11. UdoGlockenklang


    Aug 23, 2006
    raal, I am pretty sure to know anything about the glock onboard pre, because I am the constructor and builder of that little thing. When you mean true bypass without volume control, than the glock is not, because in passive mode you can still use the volume and pu-balance pot. If you mean true bypass still using the volume, than it is a true bypass pre, because in passive mode, the signal is routed directly from the volume to the jack and no other electronics in that way.
    Hope that will help you.
    punchdrunk likes this.
  12. RichSnyder

    RichSnyder Columbia, MD Supporting Member

    Jun 19, 2003
    I guess the best test would be to remove the battery, put it in bypass modes and then you can see if it's true bypass.

    This reminds me that I need to get my 2 band Glock preamp put into my bass.
  13. Chasarms

    Chasarms Casual Observer

    May 24, 2001
    Saint Louis, MO USA

    I was going to suggest an Audere as well. They are extremely transparent. I installed one in a Lakland (that I regret selling) and in the neutral position, it sounded identical to passive mode to my ears.
  14. xk49w


    Apr 13, 2008
    G&L ASAT and its ilk. It is a totally passive p/u tone control with an active buffer following it. I hear only an increase in gain (and noise?) with the pre engaged. The amp does have some sort of shelved bottom boost but it is not very much, maybe 6 dB?