46 results about "Digital speaker" patented technology

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.

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 invention discloses a multi-bit Delta-Sigma modulation-based digital speaker system implementation method and device. The method comprises the following steps: 1) converting digital input formats; 2) performing oversampling interpolation filtering; 3) performing multi-bit Delta-Sigma modulation; 4) encoding a thermometer; 5) performing multi-channel mismatch-shaping; 6) converting encoding formats; 7) performing multi-channel digital power amplification; 8) driving a speaker array or a multi-voice coil speaker unit to phonate. The device comprises a digital input interface, an oversampling interpolation filter, a multi-bit Delta-Sigma modulator, a thermometer encoder, a multi-channel mismatch-shaper, an encoding format converter, a multi-channel digital amplifier, and a speaker array or multi-voice coil speaker unit which are sequentially connected. By adopting the method and the device, the high-power output under low-voltage power supply can be realized; the power consumption is reduced; the single chip integration of a multi-channel playback system is realized; the volume weight and the implementation cost of the system are reduced; the quality of playback voice is improved.

The invention relates to a digital loudspeaker drive method and a device based on quaternary code dynamic mismatch reshaping. The method comprises the steps of (1) conducting input format conversion, (2) conducting multi-bit sigma to delta modulation, (3) conducting thermometer code conversion, (4) conducting dynamic mismatch reshaping processing, (5) conducting channel data combination and mapping coding, (6) controlling metal-oxide-semiconductor field effect transistor (MOSFET) pipe of a full-bridge power amplifier network to conduct opening and closing status switching, and driving a digitalized loudspeaker load to produce sound. The device comprises a sound source (1), a digital format converter (2), a multi-bit sigma to delta modulator (3), a thermometer coder (4), a dynamic mismatch reshaper (5), a channel data combiner (6), a mapping coder (7), a multi-channel digital amplifier (8) and the digitalized loudspeaker load (9). The units are sequentially connected in order. According to the digital loudspeaker drive method and the device based on quaternary code dynamic mismatch reshaping, use efficiency of an amplifier pipe and the load is improved, development periods and hardware implementation cost are saved, and good immunity is provided for frequency response deviation of digital channels.

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.

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.

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.

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.

Conventional analog loudspeakers have a limited dynamic range as compared to the available dynamic range of digital recordings. Digital recordings use up to 24 bits and this implies a dynamic range of 141 dB. Digital loudspeakers, involving 2^N single bit devices (with N=24, this number is 1.7×10⁷) have been proposed. The present improvement is the provision of at least one loudspeaker, a plurality of analog drivers and the audio input supplied to a control processor which in turn drives one or more of the plurality of independent analog drivers. The number of drivers in operation at any one time is determined by the amplitude of the input audio signal to the control processor.

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, in which at least one of the thin-film electrodes is divided into a plurality of regions having the same area, and the respective regions are coupled in parallel and grouped to correspond to a weight of each bit digit of a parallel PCM digital signal. Thus, an electro-acoustic conversion film by which a digital speaker in which reverberation or crosstalk between segments is suppressed is obtained is provided.

The invention discloses a professional power amplifier with a DSP (digital signal processor) digital speaker processor. The professional power amplifier comprises a case, a front panel and a rear seal plate and is characterized in that a power steady-pressure plate, a power transformer, a power amplifier and a fan are arranged in the case, a DSP digital speaker processor, a signal input module, a computer interface module and a loudspeaker output module are fixed on the inner side of the rear seal plate, and the computer interface module is provided with an RS485 or USB (universal serial bus) port; the rear seal plate is provided with a power input socket, a power insurance tube socket and a radiating hole thereon; the front panel is provided with a DSP liquid crystal displayer, a volume control knobs, function selection keys and a power switch thereon. Compared with the prior art, the professional power amplifier has the advantages that installation space can be effectively reduced, funds for purchasing singular peripheral audio equipment are effectively saved, troublesome installation and debugging are omitted, convenience in management is achieved, the professional power amplifier can be connected with a computer, and the power amplifier can be better managed.

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.

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.

The invention relates to a power line transmission multiple sound track digital speaker system comprising an emitting apparatus and a receiving apparatus, wherein wherein the emitting apparatus comprises an AD conversion circuit, a coding circuit and an output coupling circuit through connection, the AD conversion circuit connects input audio signals and the input end of the coding circuit, the coding circuit is provided with a RS422 drive, the output coupling circuit is connected to the power transmission line.

A method of operating a speaker system including a speaker coupled to an amplifier, and a dedicated digital speaker protection circuit includes turning on the amplifier in a mute mode, after a first delay period, issuing a play command to the amplifier to place the amplifier in a play mode, but without an input signal during a second delay period, and performing a speaker offset detection during the second delay period, wherein, if there is an offset, then the amplifier is forced back into the mute mode, and if there is no offset, then the amplifier is allowed to continue to operate in the play mode. The method also includes issuing a speaker protection control signal or command if an offset is detected.

The invention provides an all-digital loudspeaker system and a working method thereof. The system comprises a digital signal processing module, a switching circuit, a digital loudspeaker and a power supply, and the digital signal processing module, the switching circuit and the digital loudspeaker are connected in sequence. The problems of ultrasonic radiation, signal distortion and poor frequencyresponse of an existing digital loudspeaker can be solved.