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Can I run my Sadowsky preamp into a power amp?

Discussion in 'Amps and Cabs [BG]' started by Knack, Jul 15, 2002.


  1. Knack

    Knack

    Mar 25, 2002
    New York City
    Technical question for all you electronics gurus:

    I am considering purchasing a power amp and running bass -> preamp -> power amp -> cabs.

    Output impedances for preamp are:

    XLR out - 600 ohm
    1/4" out - 10K

    But the output level is subject to the Volume control. I am considering running it into a Carvin DCM1001, which has an input impedence of >20K ohms, balanced.

    According to Roger Sadowsky: "My preamp is not designed to go straight into a power amp. It probably will work, but that is not the intended application."

    Question: How can I determine if it WILL work without incident? Should I not even consider this? Also, how is it that the SansAmp pedal can run into a power amp if it also has volume-affected outputs?
     
  2. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Hi Knack,

    It might be able to, depending on its maximum output voltage.
     
  3. Fuzzbass

    Fuzzbass P5 with overdrive Supporting Member

    Try it and see? Seriously: it won't hurt, but unless you have a very powerful amp there's a good chance the pedal won't push it hard enough to achieve gig volume (the voltage issue that Bob Lee mentioned).


    Actually, some users have to modify their SABDDI pedals to produce enough voltage.

    The SABDDI and Sadowsky devices are referred to as preamps, but provide limited volume boost. I personally would not use the SABDDI (or Sadowsky) alone with a power amp. A good compressor could function as a preamp, leaving the pedal to perform its primary role, which is tone shaping.
     
  4. bben

    bben

    Feb 28, 2002
    Santa Fe, NM
    Well, I can say from personal experience that a Sadowsky preamp will not drive a QSC PLX1602 or Stewart World 1.2 to any but low/moderate volume levels.

    On the other hand, it works fine when used into the return jack on a GK1001RB.

    You won't hurt anything by trying.

    FWIW, I found that a Fodera 2000 preamp wouldn't really drive the QSC, either. As stomp-box preamps go, it's a good one and has a reputation for having lots of gain.

    The moral of the story seems to be that you need a real, AC-powered preamp to drive a PA amp for bass, even with an active bass.

    (Side note: I put my Sadowsky preamp in my new ash/maple Lakland 55-01. It sounds great, just like it did in my MTD Beast. I love the Sadowsky preamp and agree with Roger that you don't need a mid control.)