The Nadi's produce two tone, one each, comprising of the Odic and Actinic nerve current forces. These currents also combine to produce a third composite tone. (I can't remember its name right now)

I suppose that overtones are also produced and, perhaps, some of the tones heard are a mixing of the harmonics of the tones; don't know for sure. If so, there may be some ultrasonic and subsonic tones that are not heard, but still perceived by our body.

Grant