PZP-1 Piezo Buffer – Installation

 
Required tools

  • Phillips (crosspoint) screwdriver, to remove electronics cavity cover
  • Crescent wrench or pliers
  • Soldering iron
  • Wire cutters
  • Wire strippers
  • Needle-nosed pliers
  • Heat gun (optional)
  • Solder wick or desoldering tool
  • Electronics solder (tin/lead, rosin flux)
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    Required skills
    Installing the PZP-1 requires some soldering, and desoldering, experience. This may not be a good project for you unless you’ve done some electronics soldering before. Cafe Walter Audio is not responsible for any damage you do to your bass, nor to the PZP-1, if you botch the install.

    The basic idea
    In the stock Fender Acoustic/Electric Precision bass, the piezo pickup is connected directly to the blend pot. You’re going to insert the PZP-1 in between the pickup and the blend pot.

    Recent changes
    Sorry, I haven’t fully updated these instructions… the latest batch of PZP-1s have a trimmer for the output level, so that you can match the level of your piezo pickup to the level of your magnetic pickup. During assembly I set it to my best guess for the Fender A/E. Your instrument might be different than mine, so feel free to experiment.

    Step by step instructions
    Note: the pictures that accompany these instructions show my bass, which happens to have been the subject of many previous experiments; so, the insides of your bass will look different. In particular, you’ll note that the inside of my electronics cavity is shielded. You might wish to do the same yourself, as long as you’re opening it up. But I’m not going to go into how to do that in these instructions.

    1. In each of the following steps, make sure to place the instrument on a soft, non-scratching surface. Whenever possible, cover the instrument with a soft cloth, so that if you drop or slip with a tool, you won’t damage the finish.

    2. Remove the knob from the blend control, by pulling it off. If you have to pry it off, be sure to protect the finish of your bass with something like a piece of cardboard.

    3. Remove the nut that holds the blend pot.

    4. Place the instrument face down and remove the cover from the electronics cavity.

    5. Remove and disconnect the battery.

    6. Remove the blend pot from the cavity, so you can get at the wires.

    7. The piezo pickup wire is the shielded wire that runs from the bridge, to the section of the blend pot that is closest to the shaft (the “front” section). Carefully unsolder both the shield and the center conductor of the piezo pickup wire from the blend pot.
    cavity_before
    8. Slide the narrow of heat shrink tubing over the piezo pickup wire, and push it a few inches down the wire so that it doesn’t heat up during soldering.

    9. Solder the piezo pickup wire to the input terminals of the PZP-1. The shield goes to the bottom hole, and the center conductor to the top hole, as shown in the picture.
    input
    10. Solder the output wires of the PZP-1 to the blend pot, where the piezo wires used to be. The green wire (ground) goes where the shield used to go, and the red wire (signal) goes where the center conductor used to be. Note that in the photos the wire colors are different.
    blend_and_pcb
    11. Slide the heat shrink tubing to the end of the piezo wire, so that it covers up the exposed shield. If you have access to a heat gun, shrink the tubing. Be very careful not to damage the finish on the bass, or melt the insulation on the wires, by applying too much heat! You can also use a flame to do this, but be very cautious.

    12. Place the large clear piece of heat shrink tubing over the entire PZP-1, and shrink it enough so that it won’t slide off, using all the same cautions as in the previous step.
    heatshrink
    13. Reinstall the blend pot. Make sure that the toothed lockwasher is on the inside of the cavity, and the smooth washer is next to the nut, on the outside.

    14. Connect the battery clip marked “Old Clip” to the old battery clip.
    clips
    15. Tuck the PZP-1 into the electronics cavity, wherever it fits best.
    installed
    16. Connect the battery clip marked “Battery” to the battery, and replace the battery in the electronics cavity.

    17. Replace the cover of the control cavity, and put the knob back on the blend pot.

    You’re done!