Overtone Vocoder

vocoder.clj

(ns test
  (:use overtone.live
        ;overtone.inst.synth
        overtone.inst.io))

(def a (buffer 2048))
(def b (buffer 2048))

(definst vocoder [freq 432]
  (let [input (in 8)
        src (mix [(saw (* 1.01 freq)) (saw (* 0.99 freq))]); synth
        formed (pv-mul (fft a input) (fft b src))
        audio (ifft formed)]
    (normalizer audio)))

(def kb (midi-in))

(def mem (atom {}))
(def logg (atom ()))

(defn assoc-once [m k v]
  (if-not (get m k)
    (assoc m k (v))
    m))

(defn midi-responder [event timestamp]
  ; my synth has no :note-off, ajust accordingly 
  (when (= (:cmd event) :note-on)
    (swap! logg conj event)
    (if (> (:vel event) 0)
      (swap! mem assoc-once
             (:note event)
             #(vocoder (midi->hz (:note event))))
      (do
        (kill (get @mem (:note event)))
        (swap! mem dissoc (:note event))))))

(midi-handle-events kb midi-responder)

What are a and b in this code?

Two buffers. I'll add them.

What fun! Sounds nice with pink noise and a bit of reverb too:

(demo 60
      (let [input    (in 8) ; mic
            src      (pink-noise) ; synth
            formed   (pv-mul (fft a input) (fft b src))
            audio    (ifft formed)
            reverbed (g-verb audio 9 0.7 0.7)]
    (pan2 (* 0.1 reverbed))))

What I want to try is to find/make a synth with a 'full' sound, and hook it up to my keyboard. Only my keyboard doesn't send :note-off signals :(

You could make a monophonic keyboard :-) Have you had a look in overtone.inst.synth for something 'full'?

I figured mine sends {:note-on :vel 0} on release. pad is fine, although I'd like it more pinchy.