Whats the difference between active and passive

Discussion in 'Basses [BG]' started by alx564, Sep 30, 2000.

  1. alx564


    Jul 31, 2000
    Emmaus, PA
    Hey I was just wondering what the difference between passive and active was. If you could please explain a little. Thanks
  2. ytsebri


    Sep 1, 2000
    Passive pickups put out a 1 volt signal to your amp. That's enough, but it can be subject to outside interference. Active pickups put out a 9+ volt signal(depending on how many batteries you have). This boosts the output so that the signal can be immune to these interferences.
  3. Gard

    Gard Commercial User

    Mar 31, 2000
    Greensboro, NC, USA
    General Manager, Roscoe Guitars
    alx -

    Welcome to TB! :)

    An active or passive bass is in reference to the electronics (tone controls) and/or pickups on the bass. Typically, an active system will allow you to both boost and cut a particular group of frequencies (highs, lows, mids),while a passive system will only reduce highs. To accomplish that, an active system has an internal preamp of some sort, which allows it to boost the frequencies, which requires power, which is usually supplied by a 9V battery (although some can use 18V or "phantom power"). Some active packages are "boost only" such as the original MusicMan StingRay basses or the Aguilar aftermarket preamp. Passives are "roll-off" only systems, as all they do is use a capacitor to "roll-off" certain frequencies, usually highs. Hope that helps some, I'm sure others will chime in with more and better info soon.

    This probably belongs in the "Pickups" forum, but since it's in GM's fief, I'll let him make that decision :D.
  4. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Thanks for pulling that all together, Gard. My only passive bass is a Roscoe Beck V, and I kept wondering why it only has one tone knob. Now I know ... to roll off the highs. But it DOES have 15 or 20 little switches all over it to diddle the pickups, giving it a phenomenal tonal range for a passive bass. I prefer active electronics with bass-mid-treble cut and boost. My Pedulla fretless has Bartolini TBT electronics that give bass and treble cut and boost, but no mid control except a mid boost switch. I'd think that you want full parametric mid, or at least semi-parametric on a fretless. That's one of the reasons why the Pedulla is for sale and the Lakland is on order. At least Lakland gives you a dip switch to control the mid frequency (but not the Q, or bandwidth).
  5. Gard

    Gard Commercial User

    Mar 31, 2000
    Greensboro, NC, USA
    General Manager, Roscoe Guitars
    Munji -

    If you're looking for an active package that gives you both sweep (Q) and boost/cut for mids, check out the EMG BQC. I've got them in both my basses, and they're great for fixing a room with funky acoustics quickly. I'm not 100% sure, but I'd think it would work fine with Bartolini or any other pickup.
  6. Quzumm


    Sep 25, 2000
    Trondheim, Norway
    What's the difference on a "on-bass" preamp and a "on-amp" preamp? Why not have a passive bass and an EQ on the amp?
  7. Part of the reason for using onboard preamps is that with the higher signal level they put out, they can drive a longer cable without being so susceptable to external noise and hum.

    Another reason is that for most folks, having the ability to do some EQ adjustments at the bass is easier than walking back to the amp to do it.
  8. Note too that there are active preamps you can use with passive basses that clip onto your belt, such as the ones from Sadowsky and Aguilar. These are a good alternative for people who don't want to hack up their classic bass to make room for an electronics package and a battery.