Abstract: An active adaptive control system and method has frequency dependent filtering with a transfer characteristic which is a function of a frequency dependent shaped power limitation characteristic maximizing usage of available output transducer authority. Band separation is provided for different tones. Power limit partitioning is provided for effectively distributing power between correction tones to maximize model performance.

Abstract: A multi-filter-set active adaptive control system includes a plurality of output transducer arrays introducing control signals to combine with a system input signal to yield a system output signal. A plurality of error transducers sense the system output signal and provide a plurality of error signals to a plurality of sets of adaptive filters. A plurality of sets of D/A converters are provided at the outputs of the adaptive filters outputting correction signals therethrough. A plurality of sets of A/D converters are provided at the filter inputs and error inputs of the adaptive filters. Various filter sets and combinations are provided.

Abstract: An active acoustic attenuation system prevents overdriving of the canceling output transducer or speaker (14) by shunting at least part of the correction signal (46) to a parallel shunt path (306) and away from the output transducer (14) Variable gains (308 and 310) are provided in the shunt path (306) and the input to the output transducer (14) for varying the ratio between the part of the correction signal (46) supplied to the output transducer (14) and the part of the correction signal (46) shunted to the shunt path (306). A first adaptive filter model (40) has an error input (202) from the error signal and outputs the correction signal (46). A second adaptive filter model (142) models the output transducer (14) and the error path (56) between the output transducer (14) and the error transducer (16).