Abstract: This invention provides a method of additive synthesis of sound wherein the amplitude A of a plurality of harmonics having frequency n*f, where f is the fundamental frequency and n is the harmonic number, is calculated by use of a formula selected from those belonging to the family described by Formula I:A(n)=P*[(1/n.sup.a)(sin)(.pi.n(X%)).sup.b (cos(.pi.n(X%)).sup.c (sin(.pi.n(X'%)).sup.b' (cos(.pi.n(X'%)).sup.c' (sin(.pi.n(X"%)).sup.b" (cos(.pi.n(X"%)).sup.c" . . . ]+Q*[(1/n.sup.d)(sin(.pi.n(Y%)).sup.e (cos(.pi.n(Y%)).sup.g (sin(.pi.n(Y'%)).sup.e' (cos(.pi.n(Y'%)).sup.g' (sin(.pi.n(Y"%)).sup.e" (cos(.pi.n(Y"%)).sup.g" . . . ]+ [I]wherein coefficients P; a; X, X', X", etc.; Q; d; Y, Y', Y", etc.; are real numbers, and coefficients b, b', b", etc.; c, c', c", etc.; e, e', e", etc.; g, g', g", etc. are non-negative integers;or Formula II:A(n)=P*[(1/n.sup.a).times..vertline. sin(.pi.n(X%).vertline..sup.b .times..vertline. cos(.pi.n(X%).vertline..sup.c .times..vertline. sin(.pi.n(X'%).vertline..sup.b' .times..