J. Phys. IV France 02 (1992) C1-105-C1-108
RÉSONATEURS CONIQUES : DESCRIPTION TEMPORELLEX. BOUTILLON and C. VALETTE
Laboratoire d'Acoustique Musicale, Université Paris 6, CNRS URA N° 868, T. 66, 5ème et, 4 pl. Jussieu, F-75252 Paris cedex 05, France
An elementary time-domain analysis of the travelling of a pressure impulse along a clarinet leads to a natural understanding of the l/4 resonance. A plain transfert to a conical bore would lead to the same but erroneous conclusion. In a conical bore the velocity turns out to be responsible for the opening of the reed after only one around trip of the impulse. The near field velocity is dominated by a term which is ruled by the local pressure. Therefore an inversion of the pressure at the open-end is sufficient to ensure an inversion of the velocity when it comes back to the apex. This understanding provides with an alternate insight on the transition between cylindrical and conical bores.
© EDP Sciences 1992