Patent ID: 9247342
Filing Date: 2016-01-26
CPC Classification: H03G,H04R

Claim Text:
1. A loudspeaker system including a multi-mode signal processor for minimizing audible overload distortion while increasing perceived low frequency output capability, comprising; at least one loudspeaker enclosure including at least one low frequency resonant chamber and at least one electro-acoustical transducer with a vibratile diaphragm for converting an input audio electrical signal into a corresponding acoustic output signal, with the resonant chamber consisting of at least one of a bass-reflex resonant chamber and a wave-resonant air-column chamber, a first frequency range with a reduced diaphragm displacement and a fundamental resonant chamber resonance frequency F a second frequency range adjacent to, and higher in frequency than, the first frequency range including an increased diaphragm displacement and a frequency F a third frequency range above the frequency F a primary dynamic narrowband filter for dynamically adjusting a gain of one or more frequencies within the second frequency range, a harmonics controller, incorporating a dynamic harmonics generator, to dynamically generate harmonics in the third frequency range creating a virtual fundamental tonal gain in the second frequency range that corresponds to the dynamically gain adjusted frequencies in the second frequency range and creating at least a partial tonal gain replacement for the gain reduced frequencies in the second frequency range, a threshold detector configured to detect a primary narrowband audio amplitude threshold corresponding to a displacement of the transducer diaphragm within the second frequency range, wherein when an audio signal level is below the primary narrowband amplitude threshold the primary dynamic narrowband filter is inactive, and when the primary narrowband audio amplitude threshold is exceeded, the primary dynamic narrowband filter is activated and the dynamic harmonics generator is cooperatively activated with the dynamic narrowband filter, and as a level of an audio input signal within the second frequency range is increased further, the gain of the primary dynamic narrowband filter is reduced and the harmonics gain of the dynamic harmonics generator is increased, and, when operating above the primary narrowband amplitude threshold the signal processor operates with the dynamic narrowband filter gain and the dynamic harmonics generator gain corresponding in an inverse relationship to each other, and as the filter gain in the second frequency band is dynamically reduced to minimize an audible overload distortion, a first frequency range acoustic level is substantially maintained relative to that of an acoustic level of the second frequency range, to more effectively maintain a perceived physical bass impact, and the harmonics gain in the third frequency range is increased to more effectively maintain a perception of a tonal level in the second frequency range.