Measurements and simulations of sung multiphonics on a trombone played by an artificial mouth
Christopher Page, Joël Gilbert, Alan Woolley, D. Murray Campbell · The Journal of the Acoustical Society of America · 2021
Playing a sung multiphonic on a brass instrument is a specialised technique in which the performer sounds one pitch through lip vibration while simultaneously singing a different pitch. The result is typically a complex sound in which several different pitches are audible. A full acoustical description of the sound generation process would include the mutual interactions of the two nonlinear flow valves (vocal folds and lips), the player’s windway resonances, and the resonances of the instrument. Velut et al. (JASA 2016) reported measurements of mouth pressure, pressure inside the mouthpiece, and radiated sound while a trombone player performed various sung multiphonics. A simplified time domain simulation model replacing vocal folds and windway by a sinusoidal source was partially validated. In the present work the human player has been replaced by an artificial mouth, allowing the “sung” mouth pressure to be provided either by a sinusoidally excited loudspeaker or a human singer. Results are broadly in agreement with those of Velut et al., and with time domain simulations using sinusoidal forcing in the mouth cavity.