53.png" alt="cos(-x)=cos(x)">,
so the negative frequency component adds to the positive frequency component if it's a cosine, but 
subtracts if it's a sine.  We get a different 
pattern of cancellations depending on the initial phases of the carrier and modulator.  Take the CLM
instrument:
</p>

<!-- CLM CASE
<pre class="indented">
(definstrument pm (beg end freq amp fm-index mod-phase)
  (let ((cr (make-oscil freq))
        (md (make-oscil freq mod-phase)))
    (run
      (loop for i from beg to end do
   