This is the THX sound synthesised using Overtone, a music synthesis program.

  (definst thx [gate 1]
  (let [target-pitches (map midi->hz [77 74 72 70 65 62 60 58 53 50 46 34 26 22 14 10])
        r-freq         (env-gen:kr (envelope [1 1 0.007 10] [8 4 2] [0 -4 1] 2) gate)
        amp-env        (env-gen:kr (envelope [0 0.07 0.21 0] [8 4 2] [0 1 1] 2) gate :action FREE)
        mk-noise       (fn [ug-osc]
                         (mix (map #(pan2 (ug-osc (+ (* r-freq (+ 230 (* 100 (lf-noise2:kr 1.3))))
                                                     (env-gen:kr (envelope [0 0 %] [8 6] [0 -3]))))
                                          (lf-noise2:kr 5))
                                   target-pitches)))
        saws           (mk-noise saw)
        sins           (mk-noise sin-osc)
        snd            (+ (* saws amp-env) (* sins amp-env))]
    (* 0.5 (g-verb snd 9 0.7 0))))

https://github.com/overtone/overtone/blob/master/examples/th... http://overtone.github.com/