Nonlinear Intermodulation of Two Coherent Acoustic Progressive Waves Emitted by a Wide-Bandwidth Loudspeaker
Résumé
A formalism is presented that could be relevant for a qualitative interpretation of nonlinear harmonic distortion and in particular, strong intermodulation occurring in air in the frequency range of 20 Hz to 20 kHz when a wave is propagating. For that purpose the one-dimensional nonlinear acoustic propagation in an infinite medium of two harmonic waves at frequencies of several hertz and several kilohertz is studied. Despite the experimental uncertainties resulting from the nature of the field emitted by the wide-bandwidth loudspeaker used, it can be concluded that intermodulation caused by the nonlinear effects when an acoustic wave propagates generates important nonharmonic distortion under usual listening conditions.