That Corporation

Analog Devices,inc.

Christopher M Hanna

Miguel A Chavez

Gregory Benulis

Robert W Moses

Shrenik Deliwala

Martin Kessler

Neal Tait Kurfiss

Scott Skinner

Eric M Cline

Tyler Ray

Leslie B Tyler

Nicholas J Jakse

Joshua Berlin

Disclosed herein are systems and techniques for audio and lighting control in a bus system. For example, in some embodiments, a bus system may be configured for operation as a light organ and/or to generate sound effects based on accelerometer data.

Audio and lighting control via a communication bus

Systems and methods for optically measuring displacement of an element include an emitter for emitting an optical signal, a first detector for detecting reflections of the optical signal from the element, a second detector for detecting reflections of the optical signal from a raised cover structure, a processor for receiving the detected reflections from the first and second detectors and removing distortions in the detected reflections from the first detector using the detected reflections from the second detector.

Optical measurement of displacement

Speakers do not always operate linearly. Linearity of the speaker can affect the quality of the sound produced by the speaker, i.e., causing distortions in the sound, if the nonlinearites are not accounted for. To determine nonlinearities of the speaker, the speaker is often modeled and measurements are made to estimate the characteristics of the speaker based on the model. By using an angle sensor and a light source, a speaker manager can make a direct measurement of excursion or displacement of the speaker. Moreover, when the angle sensor, the light source, and the light beam are configured appropriately with respect to the moving cone of the speaker, the measurement can be substantially linear with respect to the amount of excursion or displacement. Such measurements are far simpler to use and in some cases more accurate than measurements made by other types of systems.

Optical and capacitive sensing of electroacoustic transducers

A disclosed system and method dynamically controls the perceived volume of a stereo audio program including left and right channel signals. The system includes a dynamic volume control that operatesto maintain a perceived constant volume level of the stereo audio program; and an excessive spatial processing protection processor configured and arranged for controlling the level of a difference signal, created as a function of the right channel signal subtracted from the left channel signal (L&#x2212;R), relative to the level of a sum signal, created as a function of the right channel signal plus the left channel signal. The excessive spatial processing protection processor processes the audio signals so as to control the difference (L&#x2212;R) signal relative to the sum (L+R) signal. A system and method are also provided for dynamically controlling the perceived volume of a stereo audio program including left and right channel signals.

Dynamic volume control and multi-spatial processing protection

Systems and methods for enhancing the low frequency response of a loudspeaker for relatively low input level audio signals and protect the loudspeaker for relatively high input level audio signals make use of a crossover network configured so separate an audio input signal into at least two frequency bands including a low frequency band; and a signal compressor responsive to the energy level of the low frequency portion of an input audio signal in the low frequency band and configured to provide amplification gain on the low frequency portion of the input signal when the energy level of the low frequency portion of the input signal is relatively low. One or more peak limiters may be positioned before the summer(s), in the circuit, but after the low band compressor. The EQ unit(s) may be positioned before all processing to the L and R inputs.

Compressor based dynamic bass enhancement with EQ

The disclosed BTSC encoder includes a left high pass filter means for receiving a digital left channel audio signal and for digitally high pass filtering the digital left channel audio signal and thereby generating a digital left filtered signal; a right high pass filter means for receiving a digital right channel audio signal and for digitally high pass filtering the digital right channel audio signal and thereby generating a digital right filtered signal; a matrix means for receiving the digital left and digital right filtered signals, and including means for summing the digital left and digital right filtered signals and thereby generating a digital sum signal, and including means for subtracting one of the digital left and digital right filtered signals from the other of the digital left and digital right filtered signals and thereby generating a digital difference signal; a difference channel processing means for digitally processing the digital difference signal; and a sum channel processing means for digitally processing the digital sum signal.

BTSC encoder

A digitally-controlled analog gain circuit supports a plurality of gain settings in which gain changes are made from a first setting to a new setting in response to a clocking signal. Large changes in gain are interpolated in small gain steps or increments. The clocking signal can be generated by an oscillator, or as a sequence of pulses output by a zero crossing detector. The gain circuit can apply positive gain to the signal. Alternatively, the gain circuit can apply a negative gain (attenuation) to the signal. The clocking signal can be provided in a pseudo-randomized manner to minimize unwanted signal effects such as discernable sound transients.

System and method for interpolating digitally-controlled amplifier gain

A disclosed system and method dynamically controls the perceived volume of a stereo audio program including left and right channel signals. The system comprises: a dynamic volume control configured and arranged so as to maintain a perceived constant volume level of the stereo audio program; and an excessive spatial processing protection processor configured and arranged for controlling the level of a difference signal, created as a function of the right channel signal subtracted from the left channel signal (L&#x2212;R), relative to the level of a sum signal, created as a function of the right channel signal plus the left channel signal; wherein the excessive spatial processing protection processor processes the audio signals so as to control the difference (L&#x2212;R) signal relative to the sum (L+R) signal. A system and method are also provided for dynamically controlling the perceived volume of a stereo audio program including left and right channel signals, comprising: a dynamic volume control configured and arranged so as to maintain a perceived constant volume level of the stereo audio program; and a program change detector configured and arranged to provide a program change signal indicating that the volume of the left and right channel signals has dropped below a threshold level for at least a threshold time period so as to anticipate a possible change in the sound level of the left and right channel signals; wherein the dynamic volume control is responsive to the program change signal.

A digitally-controlled analog gain circuit supports at plurality of gain settings in which gain changes are made from a first setting to a new setting in response to a clocking signal of a non-uniform rate. The non-uniform rate clocking signal can be created pseudo randomly by applying a periodic sequence of clock pulses to a linear feedback shift register. Alternatively, the non-uniform rate clock signal can be created by applying a noise source to a phase detector input of a phase locked loop. The clocking signal can be generated by an oscillator, or as a sequence of pulses output by a zero crossing detector. Finally, the gain circuit can apply positive gain to the signal. Alternatively, the gain circuit can apply a negative gain (attenuation) to the signal.

Growing community of inventors

Arlington, MA, United States of America

Christopher M Hanna