active, passive, what is it?

Discussion in 'Pickups & Electronics [BG]' started by king_truffle, Aug 29, 2001.

  1. king_truffle


    Apr 4, 2001
    Oshkosh WI
    Ok, first off, this isn't another active vs. passive thread. I hear all this talk about active this and passive that. What does it all mean? What exactly is an active bass, versus a passive one? I'm probably an idiot but nobody ever explained it to me. Any help would be nice. Thanks gang.
  2. Flatwound

    Flatwound Supporting Member

    Sep 9, 2000
    San Diego
    An active bass has a preamp built into it. The preamp could be in the pickups, or separate from them, or in some cases, both. Passive basses produce their sound without built-in preamps. Active basses usually use batteries, though some have been built that use an exterior power supply.

    Both types send a signal to the amplifier that is generated by the movement of the strings through a magnetic field. An active bass amplifies this signal before it gets to the instrument cable. A passive bass just sends the signal through the cable to the amplifier.

    This is a very simplified explanation, and there are some exceptions, such as piezoelectric transducers and the Lightwave system, but it should suffice to answer your question.

    Hope this helps.
  3. Bass Guitar

    Bass Guitar Supporting Member

    Aug 13, 2001
    An active bass usually means a bass with active preamp and passive pickups. The active preamp allows you to boost the bass and treble of the tone, whereas in a passive bass without a preamp you can only cut the bass and treble, not boost. An active preamp also helps to boost the signal when you use a long cable, as oppose to a passive bass when you can get signal loss with long cables. An active preamp can also fix up the impedance mismatch when you plug in your bass into a mixer for recording.
  4. king_truffle


    Apr 4, 2001
    Oshkosh WI
    Ok, cool, thanks guys. It all makes sense now.
  5. If it uses batteries, (9 volt - one or two batteries), it is active. ;)