SoundHack: A Brief Overview

Abstract

SoundHack is a sound-file processing program for the Apple Macintosh. When I started writing it in 1991, there was very little signal-processing software available on the Macintosh. Because my first exposure to computer music was at the Computer Audio Research Lab in San Diego, I wanted to have programs like Mark Dolson's pvoc and convolvesf (Moore, Loy, and Dolson 1983) on a computer that I could afford. By implementing spectral soundprocessing algorithms on the Macintosh, I was able to take advantage of the computer's graphical user interface to make the algorithms easy to use and understand. My intention with SoundHack has been to make sophisticated sound processing available on this inexpensive, intuitive computer and, consequently, to make it accessible to most composers. In the five years since its inception, SoundHack has gone from a simple sound-file filter and format converter to a mature program with a rich set of signal-processing and sound-file utility functions. The processing algorithms now include binaural filtering, sound-file convolution, spectral-dynamics processing, gain scaling, spectral mutation, the phase vocoder, varispeed, spectral extraction, and spectral analysis/resynthesis. Most of these algorithms are based on the well-known windowed FFT/IFFT analysis/resynthesis technique and a simple inputfilter-output signal-flow structure. In this article, I will give a brief tour of my program, showing its unique features and the working environment it presents to the user.