Patent ID: 6731760
Filing Date: 2004-05-04
Classification: H04R

Abstract:
A method for controlling a loudspeaker system in a room, said method comprising the steps of:(a) determining, in a first acoustic environment, a first resultant acceleration, velocity or displacement of a driver diaphragm of the loudspeaker system, and a first sound pressure in front of and in close proximity of said diaphragm; (b) determining, based on said first sound pressure, a first associated force, arising from a first sound field in the first acoustic environment, acting on the driver diaphragm; (c) determining, based on said first acceleration, velocity or displacement and said first associated force, either a first acoustic radiation resistance of a first radiation impedance experienced by said driver diaphragm, a first radiated acoustic power from said driver diaphragm, or a first real part of a first acoustic wave impedance near the driver diaphragm in the first acoustic environment; (d) determining, in a second acoustic environment, a second resultant acceleration, velocity or displacement of the driver diaphragm of the loudspeaker system and a second sound pressure in front of and in close proximity of said diaphragm; (e) determining, based on said determined second sound pressure, a second associated force, arising from a second sound field in the second acoustic environment, acting on the driver diaphragm; (f) determining, based on said second acceleration, velocity or displacement and said second associated force, either a second acoustic radiation resistance of a second radiation impedance experienced by said driver diaphragm, a second radiated acoustic power from said driver diaphragm, or a second real part of a second acoustic wave impedance near the driver diaphragm in the second acoustic environment; (g) determining a ratio between either said first and second radiation resistances in the first and second acoustic environments, or between said first and second radiated acoustic powers in the first and second acoustic environments, or between said first and second real parts of the first and second acoustic wave impedances, respectively, near the driver diaphragm in the first and second acoustic environments; (h) inserting a controllable correction filter in a signal path to said driver; and (i) adjusting parameters of the controllable correction filter using said ratio, whereby the performance of said loudspeaker system in said second acoustic environment substantially matches the performance of said loudspeaker system in said first acoustic environment.