#Avocoder: An Interface for Tangible Voice Manipulation
Sravanti Tekumalla and Galen Chuang
Created for MUS378: Deconstructive Audio, Professors Jenny Johnson and Nicholas Knouf
Presented at the Ruhlman Conference 2015 at Wellesley College
Avocoder is a musical interface created for MUS378: Deconstructive Audio. Built with Arduino and Max/MSP, our interface allows people to manipulate their voices by tangibly varying pitch, volume and distortion. Modern musical synthesizers come with a myriad of preset patches and filters to alter pitch and voice, and that abstraction creates an environment for passive interaction. We aim to give people the chance to directly manipulate parameters of sound with their hands and voice, allowing them to explore sound beyond the paradigm of rigid systems. We hope that people will take away an experience of playing with digital sound and the sound of their own voice in ways they hadn’t before, and that Avocoder encourages them to challenge predefined constraints of modern musical software.
Our project was inspired by the vocoder, a synthesis technique used to reproduce human speech. The vocoder was originally developed for telecommunication purposes in the 1930s, using the ideas of “codifying” speech and encrypting sound to avoid interception by third parties. The vocoder works by performing digital signal processing to modify the voice input, measuring how its spectral, or ghost-like, characteristics change over time. Avocoder uses a similar technique to manipulate voice (or voices).
Note: to use these patches, download MAX/MSP. These patches were developed on versions 6 and 7.
There are two modes:
Uniform pitch – voice is set to two uniform pitches.
Relative pitch – every pitch in the voice is shifted by a defined value.
Two knob inputs are shown at the top, and calculations are performed on the data. Then, the data are converted into two audio signals, which are then fed back into the main patch.
Audio signal from microphone 2 is inputted and converted into non-audio data, which are used to modify the output of microphone 1.
