l carrier
		           (+ vib 
			      (* (env indf1) (oscil fmosc1 vib))
			      (* (env indf2) (oscil fmosc2 (* 3.0 vib)))
			      (* (env indf3) (oscil fmosc3 (* 4.0 vib)))))))))))

(with-sound () (violin 0 1.0 440 .1 1.0))
</pre>
<!-- -->


<p>There is one surprising aspect of the parallel FM equation.  Since we can fiddle with the initial phases of the modulating signal's components,
we can get very different spectra from modulating signals with the same magnitude spectrum.  In the next two graphs, 