 (fm 0 10000 1000 .25 .1 1.0 0 (* .5 pi) (* .5 pi) 0))
</pre>

-->

<!-- SND CASE -->

<pre class="indented">
(define (pm-cancellation beg dur carfreq modfreq amp index)
  (let* ((cx 0.0)
	 (mx 0.0)
	 (car-incr (hz-&gt;radians carfreq))
	 (mod-incr (hz-&gt;radians modfreq))
	 (start (seconds-&gt;samples beg))
	 (stop (+ start (seconds-&gt;samples dur))))
    (do ((i start (+ i 1)))
	((= i stop))
      (outa i (* amp (- (* (cos cx)  ; cos * sum-of-cos
			   (sin (* index (cos mx))))
			(* (sin cx)  ; sin * s