536results about "Transducer circuit damping" patented technology

An audio processing system for a listening device includes an input device, a voice activity detector and a ratio-based attenuator. The input device is configured to receive a first audio signal emanating from an environment and including a signal of interest. The voice activity detector is configured to generate a control signal in response to the first audio signal. The ratio-based attenuator is configured to receive the control signal and determine whether the signal level of the first audio signal exceeds the signal level of an audio signal received from an audio playback device by at least a target difference. If so, then the audio level of the playback audio signal is maintained. Otherwise, the audio level of the playback audio signal is adjusted, where, at the adjusted value, the first signal level exceeds the playback signal level by at least the target difference.

Described is a unit for amplifying and processing audio signals for driving an electro-acoustic transducer (D), comprising: an input for audio signals; a processor for audio signals (107); an output for a signal for driving said electro-acoustic transducer; and an input for at least one operating quantity of the electro-acoustic transducer. The audio-signal processor is programmed for setting a series of parameters defining a transducer to be emulated, the parameters of which define a model of the transducer to be emulated. The input audio signal is processed on the basis of said at least one operating quantity of the electro-acoustic transducer to obtain a behavior of the electro-acoustic transducer that emulates the transducer defined by said series of parameters set.

A loudspeaker system with a transducer and an enclosure with at least one resonant chamber, including a resonant-chamber resonance frequency, at which a displacement characteristic of a vibratile diaphragm of the transducer has a minimum. The loudspeaker system further includes a multi-mode signal processor with a set of signal processes wherein in one example, a variable gain, frequency selective dynamic filter reduces the gain in a high displacement frequency range upon an output in the frequency range exceeding an overload amplitude threshold. The gain reduction is compensated for by complimentary frequency generating signal processes, including at least one of a harmonics generator and a transpositional gain controller, with the signal processor adapted to match the resonant chamber enclosure by substantially maintaining or increasing acoustic output at the resonant chamber resonance and generating harmonics associated with fundamental frequencies in the gain reduced frequency range to maintain a perception of tonal quality and physical bass impact, increasing low frequency capability while minimizing audible overload distortion.

Loudspeakers can be damaged by high drive signals. One reason for this damage is an excess vibration displacement of the coil-diaphragm assembly. This invention describes a novel method for limiting this displacement by a signal processor. In the present invention, a low frequency shelving and notch filter is used to attenuate low frequencies according to a prediction of the loudspeaker displacement. A novel method for calculating coefficient values for a digital implementation of the low frequency shelving and notch filter according to the predicted displacement is described.

An apparatus for improving a perceived quality of sound reproduction of an audio output signal is provided. The apparatus has an active noise cancellation unit for generating a noise cancellation signal based on an environmental audio signal, wherein the environmental audio signal has noise signal portions, the noise signal portions resulting from recording environmental noise. Moreover, the apparatus has a residual noise characteristics estimator for determining a residual noise characteristic depending on the environmental noise and the noise cancellation signal. Furthermore, the apparatus has a perceptual noise compensation unit for generating a noise-compensated signal based on an audio target signal and based on the residual noise characteristic. Moreover, the apparatus has a combiner for combining the noise cancellation signal and the noise-compensated signal to obtain the audio output signal.

A method for echo cancellation in multichannel audio signals includes receiving a plurality of time-domain signals, including multichannel audio signals and at least one reference signal, transforming the time-domain signals to K under-sampled complex-valued subband signals using an analysis filter bank, and performing, for each of the K under-sampled complex-value subband signals, linear echo cancellation of the reference signal from each channel using an acoustic echo canceller. A probability of acoustic echo dominance is produced using a single-double talk estimator, and a semi-blind multichannel source separation is performed based on the probability and independent component analysis (“ICA”) to decompose the audio signals into a near-end source signal and a residual echoes using subband semi-blind source separation. The residual echo components are removed from the near-end source signal using a spectral filter bank, and the subband audio signals are reconstructed to a multichannel time-domain audio signal using a subband synthesis filter.