 (do ((i start (+ i 1)))
         ((= i end))
       (outa i (* amp 
                  (oscil cr (* fm-ind0 
                               (oscil md (* fm-ind1 
                                            (oscil ca))))))))))	

(with-sound () 
  (cascade1 0 1.0 2000 .25  500 1.5 (* 0.5 (+ pi (hz->radians 500)))  50 1.0 (+ pi (* 0.5 (hz->radians 550)))))
				      
-->

<p>The resemblance of cascade FM to parallel FM is not an accident:
</p>

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