Wanting to do the same
Hey nice! What program did you use? I've been wanting to do a similar thing for the Portal theme song.
Sorry It took a while to respond, I don't usually look back at my old pieces.
I sampled my own voice with CoolEdit Pro, at various pitched with aid of piano, then imported them into DirectWave (melodic) and FPC (Percussive) plugins in FL Studio 6.
If you procure FL and would like a copy of my Vocal Drumset, you are welcome to it. Just send me a PM.
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