Sunday, January 10, 2010

Trombone Controller - Prototype Taking Shape

This weekend, I had two thoughts about the design of my trombone controller, while watching Media Lab's Podcast (LabCast) about the Chameleon Guitar.

Thought 1: While the instrument they built is very different from the one I'm building, what struck me was the statement:

"Computers have radically changed our lives over the last fifteen years. However, the design of the electric guitar has hardly changed in the last fifty. Is this because musicians respond more to tradition, than to innovation, or, is it because the right interface has yet to be developed? (emphasis mine). The project argues that combining the unique traditional values of established musical instruments with modern technology can open the door to a myriad of new opportunities.

This resonated well with me, and it's encouraged me to finally write down a "manifesto" that captures my ideas about musical instrument design (the last three points are more about open source).

The instruments I design should:
  • reward the mastery of the performer. It should be possible to become a virtuoso on one of the instruments I design.
  • translate gesture well for skilled performers. This might mean that an instrument is idiomatically "correct" for a performer familiar with a traditional instrument. Or it might mean that a musically skilled person can instinctually control my instrument in a way that is pleasing both to the performer and her audience.
  • be reproducible by others. This means that all software and hardware will be open source.
  • encourage further experimentation and extension.
  • not impose any restrictions on their use. I want performers of instruments of my design to be able to do anything they wish with the music they make.
Thought 2: There is a lot of value in making the instrument beautiful to look at and pleasing to touch.

This thought occurred to me while watching the section in the Media Lab video where they describe how they collaborated with a string instrument builder to build the neck and body shell of the instrument.

My first thoughts about my instrument's design centered around metals, which makes sense when you consider that I spend years blowing air into a hunk of brass. But once I saw the Media Lab video, it occurred to me that there's no really good reason that I couldn't build the thing out of wood. And, given that, there's no reason I couldn't find someone with woodworking skill to make the final product really beautiful, and furthermore, there's no reason I couldn't make an interesting prototype myself, using some simple tools.

So, this afternoon I went to Home Depot and bought a 6-foot long section of 1 x 2 pine, a 3/4" dowel, and a SurForm tool, and stopped at Fry's Electronics and bought a connector I thought would allow the SpectraSymbol sensor to plug in (soldering directly to the leads would certainly destroy it).

Then, this evening I spent about an hour forming the 1x2 into the "slide" of my trombone controller prototype out of that 1x2. The slide ends up looking more like the fingerboard of a string instrument than a trombone slide(see photo). The player places his/her index finger on the top, where the sensor is, and the thumb underneath. Here's a (not very good) photo of the result, clamped to my workbench for testing (click to view a larger image):

The SpectraSymbol sensor is great - only a very light pressure is required to maintain a reading, and it seems to have very little jitter when I run a sketch that prints the values on an analog input pin.

I then hooked up the set of momentary switches I use as a temporary overtone selector, and tried to play a major scale. It's glitchy, but clearly recognizable as an ascending/descending scale. I'll be addressing the glitchiness later in software.

Next up: get the breath sensor attached to the prototype, and then figure out how to let the player control the overtones with the left hand.


  1. Jeez Gorn....impressive shit!


  2. Have you checked out the EigenHarp?

    It exhibits some of the things you talk about. I have one ordered that is supposed to arrive later this month.

  3. I have - it's quite an ambitious design. Which of the models did you order, Pete?