title: Measurements and time-domain simulations of multiphonics in the trombone.
abstract: Multiphonic sounds of brass instruments are studied in this article. They are produced by playing a note on a brass instrument while simultaneously singing another note in the mouthpiece. This results in a peculiar sound, heard as a chord or a cluster of more than two notes in most cases. This effect is used in different artistic contexts. Measurements of the mouth pressure, the pressure inside the mouthpiece, and the radiated sound are recorded while a trombone player performs a multiphonic, first by playing an F3and singing a C4, then playing an F3and singing a note with a decreasing pitch. Results highlight the quasi-periodic nature of the multiphonic sound and the appearance of combination tones due to intermodulation between the played and the sung sounds. To assess the ability of a given brass instrument physical model to reproduce the measured phenomenon, time-domain simulations of multiphonics are carried out. A trombone model consisting in an exciter and a resonator nonlinearly coupled is forced while self-oscillating to reproduce simultaneous singing and playing. Comparison between simulated and measured signals is discussed. Spectral content of the simulated pressure match very well with the measured one, at the cost of a high forcing pressure.
authors: Laboratoire de Mécanique et d'Acoustique, Centre National de la Recherche Scientifique, Unité Propre de Recherche 7051, Aix Marseille Univ., Centrale Marseille, F-13453 Marseille cedex 13, France.
authors: Lionel
authors: L
authors: Velut
authors: Laboratoire de Mécanique et d'Acoustique, Centre National de la Recherche Scientifique, Unité Propre de Recherche 7051, Aix Marseille Univ., Centrale Marseille, F-13453 Marseille cedex 13, France.
authors: Christophe
authors: C
authors: Vergez
authors: Laboratoire d'Acoustique de l'Université du Maine, Unité Mixte de Recherche - 6613, Centre National de la Recherche Scientifique, Avenue Olivier Messiaen, 72085 Le Mans cedex 9, France.
authors: Joël
authors: J
authors: Gilbert