Piezo-only wiring

Discussion in 'Luthier's Corner' started by Fasoldt Basses, Jan 10, 2006.

  1. Fasoldt Basses

    Fasoldt Basses

    Mar 22, 2005
    Stevens Point, WI
    Karl Thompson, Builder (Formerly Fat Karl)
    I'm wondering what is necessary for the wiring of a single piezo pickup. Specificaly, what do I need as far as a buffer (?) or a preamp? I don't necesaraly want an eq, but I don't want to have a weak, "quacky" signal. I had a look and search through the MIMF forum and was completely confused by their smartness. :eek: :confused:
    Is there something simple I can wire up which will make my output normal impedence and not bad-sounding?
    Oh dear, after 5 years of building basses, I'm starting to see just how little I know.:meh:
    Thanks for the help.
  2. Ok, this is guitar experience speaking, but some of it might fit.....

    I put a LR Baggs X-bridge into a strat with 3 lil killer mini H/Bs from GFS.

    There is a stereo output with the magnetic pups going one side & the piezo the other. I got a Under saddle acoustic piezo with a preamp/graphic controller. The piezo went into a 12 string, and the preamp graphic went into a floor mounted switch box for the mag/piezo pups.

    Volume wise the X bridge is similar to the mag pups BEFORE the preamp.

    Obviously it'll depend on the piezo you're using........

    I've just realised that in 25 years I've modded the life out of a load of electrics 6 strings, but until I started building my current project The most I'd ever done to a bass was fit strap locks!!!
  3. paintandsk8

    paintandsk8 Pushin' my soul through the wire...

    May 12, 2003
    West Lafayette, IN
    A buffer of some sort is definetly a good idea. Without one, the differing impedances of the different equipment you use it with could cause changes in your sound. There are several commercially available piezo buffer circuits. I have used the fishman "Powerjack" before. It is a small buffer only preamp with no controls. It would not be hard to wire a volume contro into it, I would put the volume control after the pre though. There are also stomp-box style units available from several companies. If you want to take a more hands on approach, there is a design for a do-it-yourself JFET buffer circuit floating around the net somewhere. Unfortunately these aren't simple little passive circuits, they do require batteries and transistors.