Some pointers from a 2003 Jun 5, NY Times article:
Mavericks, Art of the States, New Music Jukebox, New Music Bazaar, Experimental Musical Instruments,

AIFF Spec, Draft AIFF-C Specs Scheme code to produce AIFF files

(define (linear-pitch-space p) (let ((lx (/ (log 2) 12)))
   (* 440 (exp (* (- p 69) lx)))))