Passive bass + boost pedal = active bass sound?

Discussion in 'Effects [BG]' started by Phaidrus, Apr 16, 2021.

  1. Phaidrus


    Oct 25, 2009
    Apologies for the naive question, I have experience neither with active basses nor with pedals, but I do like the sound of active basses for certain applications.

    My question is, can one get the sound of an active bass (generally speaking) with a passive bass by using a boost effect pedal? Like the EHX The Mole or the LPB-1 or some other pedal.
  2. franklindayala


    Feb 8, 2015
    I love passive basses and also have a RC bass Booster by Xotic. It is a very transparent Unit and gives you more volumen with the option of bass and Treble knobs.

    In the past I had basses wth active pickups and preamp. The Xotic Booster Will give you what you need by an active bass.
  3. whoismarykelly


    Feb 12, 2004
    'Active' basses often have passive pickups with an active EQ that allows for cutting and boosting certain bands. The result may be a louder bass, but not like what a simple transistor booster gives you which is many db of boost. A graphic EQ pedal is a better option for giving your passive bass some of those active bass sounds.
    crapusername, obimark, smogg and 3 others like this.
  4. Kestrel


    Sep 21, 2009
    A dedicated Boost pedal, EQ pedal, overdrive (such as the EHX Bass Soul Food), or even a preamp pedal can be used to boost your passive bass’ signal to match that of your active bass’ volume. The advantage of an EQ or preamp/od pedal is that you can shape the overall tone of your bass whilst boosting its signal.
    Phaidrus likes this.
  5. JRA

    JRA my words = opinion Gold Supporting Member

    i have way more experience with active axes than i do with pedal options (disclosure: these days i'm playing passive axes), but: i was never able to get the EQ/tone options from pedals that my actives (EMG systems) gave me...close sometimes: but no cigar. (IME/YMMV)
  6. saltydude


    Aug 15, 2011
    boston CANADA
    I’m using a Transboost pedal.
    It’s a 9-18V doubler with my passive basses. I couldn’t live without it now. Allows all my other effects to work strong and as intended.
    Phaidrus likes this.
  7. Phaidrus


    Oct 25, 2009
    Excuse my ignorance but given that an active bass has passive pickups plus an onboard preamp that cuts/boosts certain frequencies, why can't one get the same results with a passive bass and the preamp and EQ controls of the amp head? Why is a second preamp on the bass itself necessary?
    lomo, bombpop14 and David McIntire like this.
  8. micguy


    May 17, 2011
    A passive bass has no buffering between the pickups and the cable's capacitive load. That gives you a filter that you can't practically undo with eq later in the chain. Putting a preamp after the cable doesn't do the same thing. The impedance of most basses is too high for that to work.

    However, if the bass is wired right (I do this in my basses, and some for clients), with certain pickups, wired for low impedance (parallel wiring) and loaded right, you can get the same effect as an active bass that way - in fact, given that you have control over what's happening before the first buffering stage, you have more possibilities for tailoring the sound than with an active bass. It can be done, but you can't get it with what's on the shelf at your local music store.
  9. mikecd1


    Mar 3, 2009
    New England
    The sansamp bass driver DI does a pretty good job at putting a preamp to work on any bass and has lots of boost for your signal along with a presence control and individual eq. Gets a tubey sound too. That would be my first choice and then there's the Sadowsky stomp box which actually IS the same preamp in their basses. Those would be my top two choices.
  10. Phaidrus


    Oct 25, 2009
    Is a standard Fender Pbass wired right, as per your description, or would it need rewiring in order to achieve the above?
  11. Medicine Man

    Medicine Man

    Apr 10, 2015
    I think the Aguilar Tone Hammer preamp is based off their OP-3 active pre? Its not going to be an exact match because of the impedence, but a lot of preamps can get close.
    Phaidrus likes this.
  12. Can you explain? I don't see how parallel wiring gives more tonal options than a three band eq
  13. Jefenator

    Jefenator Supporting Member

    Aug 22, 2008
    I got the Sadowsky stomp box to "activate" some of my passive basses. But it doesn't get used very much.
    For that modern "active" sound, I have a couple of active basses. I like the convenience of having the active tone controls right on the instrument and a buffered signal coming right out the jack. I use the passive basses to their strengths and if I want to add a bit of active EQ the amp often has it.
    YMMV - outboard preamps are definitely a thing these days with plenty to choose from.
    Phaidrus likes this.
  14. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    micguy's rewiring solution is technically correct, but for most of us, using a short cable (10 feet or less) to a preamp pedal (ahead of any other pedals, as well as the amp) is good enough to get the "active sound". This pedal is the poster boy for that:


    That pedal is literally the same preamp circuit that Sadowsky puts into their basses.

    As mentioned, the SansAmp Bass DI plus it's competitors do the job if you turn off the amp emulation, as do preamps sold by Fishman and others aimed at players of acoustic instruments.


    A preamp of any kind between the bass and amp is never necessary. It's strictly an option to obtain different sounds. It's about the voicing of the preamp and the buffering effect.

    For example, the Sadowsky 2-band boost-only EQ sounds a lot different than the EQ sections of most ampliifiers. Both of the bands cover a much wider rnage of frequencies, both stretching well into the midrange. Modern amp EQs are designed to have less interaction between bands, unlike the old Fender tube amp EQ which (surprise!!!) is more like the Sadowsky.
    Scott Lynch and Phaidrus like this.
  15. KJMO


    Feb 6, 2015
    Like mic guy said, even if you have the same preamp as a pedal, the high frequencies have been reduced by the time the signal gets there. It's gone, lost forever. With a built-in preamp, you don't have that loss, so you get more clarity and frequency range. Some people don't like that, and there is even a circuit on some wireless systems to "model" the cord, basically by reducing high frequencies.
    But to get the active bass sound, the preamp has to be close to the pickups, without the cord between.
    spatters, yodedude2 and Phaidrus like this.
  16. Phaidrus


    Oct 25, 2009
    So to get the "active sound" (with a passive bass) one needs such a pedal preamp (like the Sadowsky) in addition to the preamp of the amp head. So basically two preamps in total, like in the case of an active bass, where there also are two preamps in total in the signal chain (one on the bass itself plus one in the amp head). The difference being how things are connected/wired in each case, which can be detrimental to the end result. The "active sound" magic seems to happen as a result of the pre amplification (at the head) of an already pre amplified signal (on the bass itself or at the pedal, which is the lesser option) from the pickups.

    @KJMO got it :thumbsup:
    Last edited: Apr 16, 2021
  17. Kbassface


    Jan 26, 2009
    Would the be the basic thought behind the Jack Casady basses... super low impedance in a passive circuit?
  18. jdh3000


    May 16, 2016
    TC mini boost or Spark Plug. The first one wont color tour tone at all, the second can if you want it to. Lots of headroom. I have active basses that I prefer running passive and using these.
    Phaidrus likes this.
  19. Killing Floor

    Killing Floor Supporting Member

    Feb 7, 2020
    Austin, TX
    Maybe not active sound from a boost but you can definitely get a richer sound or more EQ from any preamp pedal.
    A preamp in your bass is the same as a preamp in a pedal for the most part.
    bombpop14 and Phaidrus like this.
  20. micguy


    May 17, 2011
    Yes - a smart Engineer decades ago (working at Alembic) was able to understand this stuff and made Jack a bass that improved certain things. It wasn’t new Science at the time, but it wasn’t yet common practice.

    Leo was a master at making something that was simple to build, and that worked fairly well. Given that, the Stingray is proof that he knew there were merits in other approaches.

    I design my instruments the way I do because, having designed pro aidio gear for decades ( our interfaces are designed for cery little interaction), using that knowledge/those practices in the service of my art makes all the sense in the world to me.