;; (pv-phase-shift270 buffer)

;; Swap the real and imaginary components of every bin at `buffer' and
;; swap the sign of the real components.

(with-sc3
 (lambda (fd)
   (async fd (b-alloc 10 2048 1))))

(let ((n (mul (white-noise ar) 0.1)))
  (audition (out 0 (ifft* (pv-phase-shift270 (fft* 10 n))))))