I thought I’d try changing the pitch of a guitar string by pulling it with a solenoid – thus “tension guitar.” I thought I’d be able to get multiple pitches by turning the puller on and off very quickly (PWM) but that didn’t work well, so I was stuck with just two pitches. That was boring, so I added a little finger that frets the string. With the combination of the two, it can play four pitches. Over and over and over, thanks to the automatic strummer. Like this. There’s also video of the various moving parts here.

thing a day 22: tension guitar from ranjit on Vimeo.

Details of the strummer, finger, and puller.

In my junkbox I found this vintage 1977 (or so) 76477 synthesizer chip- this model used to be used in arcade machines. It was gonna be another Matchbox Synth – you can see I have the case all prepped – but, whether because it’s old and broken, or because I wasn’t using it right, I couldn’t get any sounds out of it except for these.

Still, you may not have seen and heard the last of Syntho ‘77!

The scraper-shaker has a graduated series of notches, an aluminum sound cone, and, of course, a walnut shell full of steel washers. It sounds like this.

It’s kind of surprising how much the little sound cone amplifies the sound.

I was inspired when I saw coconuts for 99c at the bodega, but when I got home it took me half an hour just to get all the delicious meat out of the nut.

I keep making instruments that are too long for my short arms to play comfortably. You’d think I would’ve learned from the rotten stick guitar.

The frets are bamboo skewers – I tuned them by ear so the tuning is kind of shaky. I might add more frets later. Note how the bamboo bridge rests on a point on the membrane (architectural vellum)- this helps to transfer the vibrations of the string. The pick is made of two layers of vellum glued together.

The coconut banjo sounds like this.

Hammered aluminum, old bbq fork with corks stuck on the tines to discourage autodisembowelment. If I’d known how much work it would be to hammer the thing and that it would turn out to sound like this, I wouldn’t have bothered!

The toehorn is made from a drinking straw double reed and a nerf missile launcher I found in the trash. It sounds pretty much like this.

(suggested use)

Gambang kayu is a xylophone used in gamelan orchestras. This thing isn’t really that much like a gambang. It’s made from rotten sticks (my favorite ingredient!), string, and a bamboo windchime that was on sale at Rite-Aid for $3.49. It sounds like this.

I carved this bowl out of some waste wood I found on the street. When I roll walnuts around in it, it sounds like this.

But the real reason I carved it is to use for hammering sheet metal into gong or cymbal shapes. Unfortunately, I don’t seem to have any sheet metal.

Yesterday’s Thing was a breath controller- blow into it to control the volume of today’s Thing: the Fish Organ, so named because the box used to contain smoked fish. And it sounds a little something like this.

The keyboard is copper tape cut to shape. It’s tuned (approximately) to the twelve tone Just scale based on 2’s, 3’s, and 5’s. When the little red plug is plugged into the "No breath" jack, the thing plays at full volume without the breath controller.

I added a fingerboard to the rotten stick electric guitar for easier fingering– it’s still only long enough to play about 5 notes. And I made the worst bow ever from another rotten stick and some waxed string. Together, they sound like this.