Me acaba de llegar un spam, bellísimo:
"heard a mile, if beaten in the open air. In pueblos toward the western part of the area, as in Balili, Alap, and their neighbors, the instrument is played differently and the sound carries only a few rods. Sometimes the player sits in very un-Malayan manner, with legs stretched out before him, and places the gang'-sa bottom up on his lap. He beats it with the flat of both hands, producing the rhythmic pulse by a deadening or smothering of a beat. Again the gang'-sa is held in the air, usually as high as the face, and one or two soft beats, just a tinkle, of the 4/4 time are struck on the inside of the gang'-sa by a small, light stick. Now and then the player, after having thoroughly acquired the rhythm, clutches the instrument under his arm for a half minute while he continues his dance in perfect time and rhythm. The lover's "jews'-harp," made both of bamboo and of brass, is found throughout the Bontoc area. It is played near to and in the olag wherein the sweetheart of the young man is at the time. The instrument, called in Bontoc "ab-a'-fu," is apparently primitive Malayan, and is found widespread in the south seas and Pacific Ocean. The brass instrument, the only kind I ever saw in use except as a semitoy in the hands of small boys, is from 2 to 3 inches in length, and has a tongue, attached at one end, cut from the middle of the narrow strip of metal."
Y no solamente es verdad, sino que, además, ¡es cierto!
O algo así (http://www.fullbooks.com/The-Bontoc-Igorot5.html)... Habrá que investigar.