I am not expert, or even minorly enlightened, on this subject, but couldn't it be possible to determine, say, the tone of voice (like the note, C flat and such. I'm not musically oriented) of a range of people, and then using that calculate the most common recurring factor in all their voices, thereby creating an "average" sound of voice. It can also then be used to determine how "normal" your voice is, based on the amount of deviation from the standard. Again, I don't really know anything about this subject but maybe one idea triggers another. Interesting piece.