Real-time additive synthesis with envelope parameter stremas: an alternative to sampling

Abstract

A sampling synthesizer uses a set of recordings for sound synthesis. A shortcoming of the sampling technique is the inability to produce complex spectral changes associated with the performer’s actions during a note. Additive synthesis, on the other hand, represents each sound as a collection of sine wave components, or partials. A wide variety of modifications are possible with additive synthesis, including frequency shifting, time dilation, cross synthesis, and sound morphing. Our real-time additive synthesis uses a set of recordings, like a traditional sampling synthesizer. Unlike a traditional sampling synthesizer, our additive synthesis models timbres as collections of bandwidth-enhanced partials (sine waves with noise) with time-varying parameters. The timbres are encoded in envelope parameter streams that can be manipulated in real time. These envelope parameter streams, which provide amplitude, frequency, phase, and bandwidth information for each partial, are the counterpart of sample streams in sampling synthesis. The talk will include demonstrations using the continuum fingerboard.