UPDATE:012808 -Added audio file profiling the stick bass minus overdubbed guitars for clarity of tone.-
UPDATE:013108 - Added Piezo transducer close-up of back side.
An electric bass is created using 1 broken bass string, 1 piezo transducer, part of a cheap wooden easel leg, and 2 metal rods from a bookshelf. A video is included to demonstrate the sound of the stick bass.
Step 1: The materials needed
Most DIYer's, I'm assuming, are pack rats like me. So having recently busted a string off my bass, I just couldn't let it go to waste. Also seeing as how I had some piezo's left over from wiring up a recent circuit bending project, the idea came to me to finally try it out.
In the corner of my workshop I spied the remnants of an old cheapy easel...the flimsy kind you can find in most department stores. It immediately looked interesting being that it had wing nuts and bolts and holes right where I needed them. Not to mention the trough on one side that I though might lend to some interesting playability aspects.
Step 2: Cut, drill and notch
Using a section of the easel leg, cut a notch into the end using a coping saw. I cut far enough down to make sure the string being wound has room to turn.
To create the nut and the bridge, I used some spare bookshelf hardware pins. I wasn't worried so much about proper scale lengths than just a fast little project, so placement is up to you. I have a problem with getting caught up into details and never seeing things through, so let's not worry so much about technicalities of proper tuning and scale lengths just yet. You can either lay them on top or do as I did and drill (haphazardly mind you) through the walls of the easel leg to seat the pins.
On the other end of the stick, drill a hole, small enough to allow only the string through. Use a small washer to keep the ball end from pulling it's way through the wood.
Step 3: Wire it up
Attach the piezo how you'd like really. I opted for speed and just tied it on with fishing line since the notches in the piezo looked inviting to be taken advantage of. You'd think speed meant something more on the lines of hot glue or something. I thought it'd probably sound like crud anyway so I didn't want to make a permanent connection. It hasn't been changed since it burped it's first sounds of "gudginess".
I then soldered my piezo leads to a female 1/4" jack. I didn't want to be limited to two feet of cable and then have to add an extension anyway.
Step 4: Fire it up!
Whether you use an amp or software, the signal needs to be amplified. The piezo is very sensitive though and operates more by vibration than the electro-magnetic pickups do by their means. This means you have to learn how to play it differently.
I used a Line 6 Toneport UX2 to record everything into Ableton Live.
I've found the slightest grasp and the subtlest touch to the string gives the best tone. It can actually be fretted after a little practice. The improvements to it's playability can go a million directions, but this was just a fun project that yielded surprising results. Have fun!