Some acoustical measurements on the Chinese musical instrument P’i-P’a

Sinusoidally driven response curves and holographic time-average vibration mode patterns were obtained for the Chinese musical instrument P’i-P’a. It was found that the frequency of the top plate resonances lie at the higher end of the range of this instrument and therefore the plate resonances have the effect of strengthening the harmonic components of the most frequently played mid-range notes. Calculation predicted a Helmholtz air resonance at 139 Hz, but experimentally the air resonance was not found, indicating a very weak air peak.