(setf *ihad* ":::jan27:ihad.aiff")

(setf *ihad* "ihad.aiff")

(set-sound-srate 11025.0)

(defun ihad ()
  (s-read *ihad*))

(defun result-file () (s-read "nyquist-temp.snd"))

(setf two16 (* 256.0 256.0))

(defun qscale (signal levels)
  (scale (/ levels two16) signal))

(defun quantize (signal levels)
  (s-save (qscale signal levels) ny:all "temp.snd")
	(scale (/ two16 levels) (s-read "temp.snd"))
)

(defun test (levels)
  (play (quantize (ihad) levels)))

;(test 256)
;(s-plot (extract 4 5 (ihad)))

;(test 16)
;(s-plot (extract 4 5 (ihad)))

;(test 4)
;(s-plot (extract 4 5 (ihad)))

(defun dtest (levels)
  (play (quantize (sum (ihad) (scale (/ 1.0 levels) (noise 15.0))) levels)))

;(dtest 16)
;(dtest 4)
;(s-plot (extract 4 5 (result-file)))

(defun resam (signal rate)
	(resample (resample signal rate) *sound-srate*)
)

(defun rtest (rate)
 (play (resam (ihad) rate)))

(defun alias (rate)
 (resample (force-srate rate (ihad)) *sound-srate*))

(play (scale 0.05 
    (fmosc c4 
           (scale 10000.0 (ramp 10)))))

Assignment:
   Question: does band-limited dither sound better?  Use resampling to
create less-than full-bandwidth noise. Use it to dither a signal of your
choice. You might need to experiment with bandwidth and amplitude. Can you
make something that sounds better than uniform (white noise) dither?