From a post by High Priest Syriax in a thread about adding anachronistic elements to a fantasy game (specifically, axes that are also magical electric guitars wielded by barbarian/bards):
The more I think about it, this is the way I would go with any "musical weapon." A series of holes and grooves along the weapon itself make sound as it is swung at varying speeds in a trained combat style. Each maneuver/attack sequence produces different notes. The location and pattern of the holes/grooves on each warrior's weapon produces a slightly different voice/quality, which uniquely identifies that warrior to the other members of the tribe. When they are fighting together they can pass short communications along the battlefield via sound, and when fighting in concert they can even weave their individual combat maneuvers/songs into an ensemble which produces greater magical/morale effects for the entire tribe and drives their enemies before them.