For some reason, Jonny and I made this wonky electro-acoustic kerjigger three weekends ago, I think. It’s called the Whackinstick and it sounds a bit like a birimbao (an Afro-Brazilian instrument used in Capoeira) and a Ehr-hu (a whiny Chinese violin-like contraption). It’s made of a piece of scrounged 2×2, some goodies from the Fastener section of the hardware store, and a high E string from a guitar. We slapped a piezo buzzer and a small speaker onto it as acoustic pickups, and they work OK, though they pick up a lot of ambient noise.
Then, a couple of days ago, for some reason (probably the same reason we made the thing in the first place), I started thinking about magnetic pickups for it. Naturally, I wanted to make them out of crap I could get for $10.
So I got some superstrong neodymium magnets at the Michael’s craft store while Carrie was looking for beads, came home, and made up a way to make guitar coils. Now, before you get excited, it’s almost 3 AM and the Whackinstick does not have a magnetic pickup yet. I made one, it’s down on my workbench, and it’s making me really think about what the fuck I’m doing up this late at night.
Apparently, you’re supposed to get between .1 v and 1 v out of the thing. I’m lucky if I get .06 v. What kind of cruel joke is this? I’ve just spent all night wrapping these things up and messing with them (testing with a powerdrill and an eyebolt to make an oscillation – there’s an instrument in there somewhere), and I get .6 of the bare minimum.
Fortunately, things are not glued together and I can retry, including just amplifying the signal and seeing what I get.
In any event, here are some websites that helped me out tonight to go from .001v to .06v.
• The guy who makes the cigar box guitars on the cover of Make Magazine that inspired the Whackinstick made these, and I wish I’d noticed that before looking everywhere else.
• Rare earth magnets are probably the best to use for this kind of project. They’re very strong for their size, and apparently you want long, skinny pickups, not short, fat ones, so neodymium is, I guess, the way to go. It’s what I was using; ceramic produced a comically small voltage.
• A Wikipedia article on the electric guitar. The image at the top of this post was very helpful.
And you know what? I’m wrapping way too little coil around the magnet. Tomorrow, more wrapping. What you hear is not a test. I’m wrappin’ to the beat.