Objective: To pinpoint the location of sound generation in a three dimensional space using a three dimensional controller.

Overview: Using the Mad Catz Real World Golf Controller, sound is controlled in the CCRMA Listening Room. The controller has two standard XY joysticks with a special added bonus of another Z dimension when the user lifts up each joystick. The CCRMA Listening Room has 16 speakers arranged in a spherical surround pattern. PureData and HID are used to extract and parse the raw controller data via USB, and convert it to OSC messages, which are then sent to ChucK. Within ChucK, the positions of the artists hands are mathematically manipulated to calculate an independent gain sent to of each of the Listening Room’s 16 speakers for each hand, a total of 32 gains.

Sound Design: For this piece, I have chosen to use low pass filtered noise, intended to be soothing and washy, as a good meditative coupling to the martial arts practice Tai Chi. As the performer moves his/her hand(s) through the space, detected gains for each channel of noise are run through a two way leaky integrator. The sound slews to the desired location quickly, but leaves very slowly, creating a smearing effect. As the hands reach outward towards the speakers, the cutoff frequency of the LPF is raised and a delay mix is increased, generating a deluge sound very similar to waves or perhaps a car driving alone after a rainstorm. The right hand is used alone, and by depressing and holding the included foot pedal a second filtered noise is controlled by the left hand, generating interesting effects.

Calculations: The gains are calculated by first finding the angle and magnitude of each joystick at its current position. Then, a projection onto each of the 8 speakers in the middle ring is taken using this angle. This data is spread out in the circle using the standard sine/cosine power relationship of the current radius. The vertical dimension is handled using another set of sine/cosine power relationships which takes into account a vertical center position and any deviation up or down from it. Phasing is definitely an issue in this fairly naive method, but can be seen as an added meditative effect, especially since we are only using filtered noise.

Code:

            - link to a simple, right hand only 3D audio localizer in ChucK

            - link to the full code for Making Waves

            - link to the PureData GolfController patch