Membrane - Interactive Speakers
by Noah Vawter and Mark Feldmeier
video demonstration of "membrane."
- Codename "Membrane" is about using speakers as interactive devices.
There are several reasons for this:
- You can feel the sound through your fingertips as well as your ears. Perry Cook identifies four different receptors
in the audio range in his book Music, Cognition, and Computerized Sound. He also mentions that instrument
players, such as trombonists, can feel the sound through their hands.
- It focuses attention on the origin of the sound, unlike the typically alienating effects of speakers.
- It is a source of fresh types of sounds and music. The music of the future! ;)
- It's fun!
- The main technology behind the project is that when you press on a
speaker, you change its impedance somewhat. This impedance can be measured
and used as a parameter in a musical process.
There are a variety of ways to implement this project, but the simplest and most
effective is to drive a
with a power amplifier. Then, across the "output" of the bridge, connect the input of an FX processor.
The output of the FX processor goes to the amplifier's input. This creates a feedback loop with nonlinearities
that amplifies the relatively small changes in speaker impedance when you press on it.
Membrane is made using
Number Six microcontroller development board
Computing Culture's Number Six