48 results about "Digital speaker" patented technology

A digital sound system suitable for a digital speaker device for directly converting analog sound by a circuit using a ΔΣ modulator and a mismatch shaping filter circuit to output a plurality of digital signals and a plurality of speakers driven by the plurality of digital signals. A digital speaker driving device includes a ΔΣ modulator, a post filter, s driving circuits, and a power supply circuit to supply power to the ΔΣ modulator, the post filter and the s driving elements and the s driving circuits are adapted to s digital signal terminals.

The present invention disclosed an all-digital speaker system device based on multi-bit Σ-Δ Modulation, comprising an A / D converter, an interpolation filter, a Σ-Δ modulator, a dynamic mismatch regulator, a differential buffer and a speaker array. The present invention takes advantage of the Σ-Δ modulation technique to effectively reduce the cost and complexity of the hardware realization of the speaker system device, thus realizing the full digitalization of the whole sound transmission link and the integration of the system device with low power dissipation and volume. Furthermore, the system device according to the present invention is provided with a better control ability on the local sound field, thus providing a better practicable method for the voice secret transmission.

Digital loudspeaker comprising a support, a plurality of first membranes suspended on the support, said first membranes being bistable, and said loudspeaker comprising actuator for each of the first membranes that can change each of the first membranes from a first stable state to a second stable state and vice versa, and a controller for controlling said first actuator.

Provided is an electro-acoustic conversion film that is suitably used for a digital speaker or the like, and that includes a polymer composite piezoelectric body formed by dispersing piezoelectric particles in a viscoelastic matrix formed of a polymer material having viscoelasticity at room temperature, and thin-film electrodes provided on both surfaces of the polymer composite piezoelectric body, and at least one of the thin-film electrodes is divided into a plurality of regions of which an area increases by 2n times (n is a natural number including 0). Thus, a digital speaker in which reverberation or crosstalk between segments is suppressed is obtained.

Described herein is a retrofit digital speaker system comprising two or more retrofitted speaker enclosures, each of the two or more retrofitted speaker enclosures (enclosures) comprising: at least one speaker; and an analog-and-digital interface adapted to receive digitally encoded audio signals, electrical power, and digital command signals, and wherein the digitally encoded audio signals, electrical power, and digital command signals are transmitted over existing two wire analog audio cables, and further wherein the two or more retrofitted speaker enclosures are wired in a daisy chain fashion, via the existing two wire analog audio cables.

An operable membrane device is provided, including a plate, a plurality of membranes suspended from the plate and being a seat of residual mechanical constraints, at least a first actuator configured to deform the plate outside its plane, second actuators, each second actuator being configured to deform a membrane outside its plane, and control electronics configured to generate second control signals at the second actuators in order to vibrate the membranes and configured to generate first control signals at the first actuator to cause a deformation of the plate so that the plate is found in the deformed state, wherein a mechanical constraint is applied to the membranes that at least reduces the residual constraints of the membranes.

Actuator apparatus for generating a physical effect, at least one attribute of which corresponds to at least one characteristic of a digital input signal sampled periodically in accordance with a clock, the apparatus comprising at least one array of moving elements each constrained to travel alternately back and forth along a respective axis in response to an alternating electromagnetic force applied to the array of moving elements, at least one latch operative to selectively latch at least one subset of said moving elements in at least one latching position thereby to prevent the individual moving elements from responding to the electromagnetic force, an electromagnetic field control system operative to receive the clock and, accordingly, to control application of the electromagnetic force to the array of moving elements, and a latch controller operative to receive the digital input signal and to control the latch accordingly.

The invention is a multi-microphone voice processing SoC primarily for head worn applications. It bypasses the use of conventional pre-amp voice CODEC (ADC / DAC) chips all together by replacing their functionality with digital MEMS microphone(s) and digital speaker driver (DSD). Functionality necessary for speech recognition such as noise / echo cancellation, speech compression, speech feature extraction and lossless speech transmission are also integrated into the SoC. One embodiment is a noise cancellation chip for wired, battery powered headsets and earphones, as smart-phone accessory. Another embodiment is as a wireless Bluetooth noise cancellation companion chip. The invention can be used in headwear, eyewear glass, mobile wearable computing, heavy duty military, aviation and industrial headsets and other speech recognition applications in noisy environments.

A method and device of channel equalization and beam controlling for a digital speaker array system includes (1) converting digital format; (2) performing channel equalization; (3) controlling beam-forming; (4) performing multi-bit Σ-Δ modulation; (5) performing thermometer code conversion; (6) performing dynamic mismatch-shaping processing; and (7) extracting the channel information to send to the digital power amplifier and drive the array sound. A device includes a sound source, a digital converter, a channel equalizer, a beam-former, a Σ-Δ modulator, a thermometer coder, a dynamic mismatch shaper, an extraction selector, a multi-channel digital power amplifier and a speaker array. Each unit connects to each other serially.

The present invention discloses a method and an apparatus for driving a digital loudspeaker based on amplitude modulation and phase modulation. The method comprises the steps of: performing modulation processing for a sound source signal to generate (2L+1) coded signals x at a level grade; performing selection processing for the coded signals x and a feedback vector signal b of M channels to generate a state vector signal s of the M channels, and then performing amplitude modulation processing for the state vector signal s to generate an amplitude modulation vector signal a of the M channels; performing shaping processing for the amplitude modulation vector signal a to generate a next feedback vector signal b of the M channels; performing phase modulation processing for the state vector signal s to generate a driving vector signal p of the M channels; and achieving electro-acoustic conversion of the driving vector signal p through a power amplification driving multichannel power amplifier and energy transducer unit. The method and the apparatus of the present invention can simultaneously adjust amplitudes and phases of various channels, thereby achieving better spatial domain directivity.

A method and device for driving a digital speaker based on code conversion are provided in the invention. The method comprises the steps of: (1) converting input format; (2) performing multi-bit Σ-Δ modulation; (3) thermometer code conversion; (4) dynamic mismatch-shaping processing; (5) pulse width modulation code conversion; and (6) controlling on / off status switching of the MOSFET of a full-bridge power amplification network to drive a digital speaker load sound. The device comprises a sound source, an input format converter, a multi-bit Σ-Δ modulator, a thermometer coder, a dynamic mismatch shaper, a code converter, a multi-channel digital amplifier and a digital speaker load which are connected to each other in sequence. By means of the device and method of the invention, the switching rate of the power tube, the power dissipation and heating generated during the switching are reduced, the sound quality and efficiency of electroacoustic restoration are improved, the volume, weight and implementation cost of the system are decreased, and the level of electromagnetic radiation is reduced. Furthermore, the device and method of the invention also have excellent immunity to the frequency response deviation of multiple digital channels.