Patent ID: 6088459
Filing Date: 2000-07-11
Classification: H04R

Abstract:
In a loudspeaker system with housing, at which the pressure of the air in the chamber which adjoins the inner surface of the front-loudspeaker's membrane is influenced by the movement of the membrane of an inner transducer built into wall means within the housing, further comprising pressure sensing means arranged within the housing to measure said air pressure, the signals produced by said pressure sensing means being used by calculating means for calculation of setpoint values of movement of said inner transducer's membrane, further comprising a controller and a power amplifier, whereby the controller forces via the power amplifier said inner transducer's membrane to move with values of movement substantially equal to said setpoint values,the improvement comprising said calculating means to produce such setpoint values of movement that said controller forces said inner transducer's membrane to move with a speed which is substantially proportional to a sum which comprises at least two summands selected from the group consisting ofa first summand which is proportional to the timely derivative of said air pressure,a second summand which is proportional to the timely integral of the deviation of said air pressure from the mean air pressure,and a third summand which is proportional to said air pressure.