Additive synthesis (now more often called ``sinusoidal modeling'') was one of the first computer-music synthesis methods, and it has been a mainstay ever since. In fact, it is extensively described in the first article of the first issue of the Computer Music Journal . Some of the first high-quality synthetic musical instrument tones using additive synthesis were developed in the 1960s by Jean-Claude Risset at AT&T Bell Telephone Laboratories [233,232].
Additive synthesis was historically implemented using a sum of sinusoidal oscillators modulated by amplitude and frequency envelopes over time , and later using an inverse FFT [35,239] when the number of sinusoids is large.
Figure G.5 shows an example from John Grey's 1975 Ph.D. thesis (Psychology) illustrating the nature of partial amplitude envelopes computed for purposes of later resynthesis.