129results about "Transducer circuit damping" patented technology

An audio system receives sounds from a local area with a set of sensors. The audio system analyzes the sounds to identify an amount of background noise in the environment. The audio system may also identify target sound in the environment, such as voice from a nearby speaker, to reinforce. The amount of background noise is then used to adaptively set a level of reinforcement for the target sound. In low-noise environments, the target sound may be minimally, or not reinforced, while in high-noise environments a reinforcement sound signal may be generated with the target sound so that a transducer array may generate reinforcing sounds for the target sound and increase its contrast with the noise in the environment. By applying the reinforcement dynamically, the system automatically adjusts for different sounds and environments.

Electroacoustic drivers that can be utilized in loudspeaker systems that utilize drivers having a magnetic negative spring (MNS). The magnets of the MNS can be arranged for radial stability and / or to provide for linear magnetic forces. A variable reluctance device can be used to vary the resonant frequency of electroacoustic driver in response to a feedback signal.

Features described herein generally relate to detecting and correcting audible distortion due to speaker port occlusion. Particularly, an audio signal is output, an impedance curve for the audio signal is calculated, a change in a resonance frequency for the speaker based on an impedance curve model for the speaker and the impedance curve for the speaker is detected, and a gain of the amplifier is set based on the detected change in the resonance frequency for the speaker.

The disclosed computer-implemented method may include applying, via a sound reproduction system, sound cancellation that reduces an amplitude of various sound signals. The method further includes identifying, among the sound signals, an external sound whose amplitude is to be reduced by the sound cancellation. The method then includes analyzing the identified external sound to determine whether the identified external sound is to be made audible to a user and, upon determining that the external sound is to be made audible to the user, the method includes modifying the sound cancellation so that the identified external sound is made audible to the user. Various other methods, systems, and computer-readable media are also disclosed.

The invention provides a construction machine and a control system of the construction machine, which can improve silence. A construction machine according to one embodiment of the present invention is provided with: a lower traveling body; an upper rotating body rotatably mounted on the lower traveling body; the cab is arranged on the upper revolving body; an outer sound collection device disposed on the outer side of the cab; an inner sound output device disposed on the inner side of the cab; and a control device that restricts the sound collected by the outer sound collection device from being output from the inner sound output device on the basis of the detection result of an object present in the periphery of the construction machine.

The present disclosure relates to "vibration and force cancelling transducer assemblies." An acoustic device is disclosed that includes a housing having a housing wall defining a housing volume; a first mass movably coupled to the housing, the first mass including a sound radiating surface, a voice coil, and a first suspension member; a second mass movably coupled to the housing, the second mass including a magnet assembly and a second suspension member, and wherein the first suspension member couples the first mass to the second mass, the second suspension member couples the magnet assembly to the housing wall, and the second suspension member is tuned to reduce housing vibrations caused by movement of the first mass and the second mass relative to the housing.

An acoustic apparatus includes a class-D amplifier including a current feedback circuit, and a speaker system including a voice coil driven by the class-D amplifier. The speaker system is configured such that, in a case where the speaker system is driven by an ordinary amplifier having a first output resistance lower than a second output impedance of the class-D amplifier, a Q factor of the speaker system falls below a predetermined lower limit of an ordinary Q factor range of an ordinary speaker system. The current feedback circuit is configured to increase the second output impedance of the class-D amplifier by feeding a current flowing to the voice coil back to an input of the class-D amplifier so as to increase a Q factor as the acoustic apparatus higher than the predetermined lower limit of the ordinary Q factor range and within the ordinary Q factor range.

The present disclosure relates to a portable device and an operating method thereof. For example, the portable device includes a microphone structure configured to convert a received audio signal into an electronic signal representing the received audio signal, and to transmit and receive ultrasonic waves by emitting ultrasonic waves and receiving reflections of the ultrasonic waves. The portable device also includes a control unit configured to evaluate the reflections of the ultrasonic waves to obtain an evaluation result, and to control the operation of the portable device based on the evaluation result.

The embodiments of the present invention provide a microphone amplifier circuit, a microphone circuit, and an electronic device. The microphone amplifier circuit comprises a first transistor, a first constant-current source, and a source follower. A gate electrode of the first transistor serves as an input end of the microphone amplifier circuit, a source electrode of the first transistor serves as an output end of the microphone amplifier circuit, and a drain electrode of the first transistor is grounded. An input end of the first constant-current source is connected to a power supply, and an output end of the first constant-current source is connected to the source electrode of the first transistor. The source follower at least comprises a second transistor. A drain electrode of the second transistor is connected to the power supply, a gate electrode of the second transistor is connected to the source electrode of the first transistor, and a source electrode of the second transistor is connected to the drain electrode of the first transistor. The present invention at least facilitates an improvement to the THD performance of microphone amplifier circuits.

Electrical circuitry adapted to drive a dual-coil loudspeaker having a primary voice coil and a second voice coil connected in parallel with the primary voice coil, the second voice coil being in series with an LC resonant circuit of impedance Zmf, further comprising an inductance compensation filter of impedance Zif in parallel with the LC resonant circuit.

The invention relates to a method and a device for controlling the propagation of sound waves in the vicinity of a wall, the method and the device implementing, by means of a control law, a master device for controlling a set of Nc elementary cells (1) mainly composed of a loudspeaker (11), a set of Nm microphones (10) connected to the loudspeaker and a control unit (12), the control law determining an electrical signal to be sent to each loudspeaker (11) to obtain a target generalized acoustic impedance determined for each loudspeaker, so that a portion of the sound waves is absorbed by the membrane of each loudspeaker (11).

The present invention addresses the problem of providing a "speaker output characteristic correction system and sound system" which correct the output characteristic of a speaker to a target output characteristic with high accuracy. [Solution] A control filter (61) convolves a sound source output signal u (n) with a reverse transmission characteristic G-that is a transmission characteristic of a sound pressure level at a predetermined sound reception point (M) and a target transmission characteristic H that is a target sound pressure level, and outputs the convolved sound source output signal through an amplifier (4). The speaker (2) is provided with a sensor (3) for detecting the displacement of the vibration system. A transfer characteristic setting unit (62) sets a reverse transfer characteristic G-in accordance with each parameter of an equivalent circuit of the speaker (2) determined on the basis of the detected displacement. Thereafter, the transmission characteristic setting unit (62) periodically determines a change in the parameter on the basis of the detected displacement, and updates the inverse transmission characteristic G-so as to match the determined changed parameter.

A method for detecting acoustic feedback in a vehicle audio system including at least one microphone and one loudspeaker. The method includes the steps of computation of an acoustic acuity indicator for each frame of a plurality of successive audio frames captured by the microphone, detection of acoustic feedback when the indicator increases monotonically for a predetermined length of time, and application of a resolution strategy when acoustic feedback is detected.Buchanan

A speaker includes: a drive-and-support part having a frame; a vibrating part supported by the frame such that the vibrating part is able to vibrate; a magnetic drive part configured to make the vibrating part vibrate; a detection magnet provided in one of the drive-and-support part or the vibrating part; a first magnetic sensor and a second magnetic sensor provided in the other one of the drive-and-support part or the vibrating part, and configured to detect a magnetic field produced by the detection magnet; and a detection circuit configured to determine a difference between a first detection output of the first magnetic sensor and a second detection output of the second magnetic sensor. The first and second magnetic sensors are spaced apart from each other in a direction in which the vibrating part vibrates.

This acoustic device comprises: a diaphragm; a movable part having coils and connected to the diaphragm; and a magnetic circuit part comprising a magnet and a yoke, generating a magnetic force acting on the coils. The magnetic circuit part has, as part of the yoke, an upper plate part having an upper surface portion extending in a direction substantially orthogonal to the direction in which the movable part is movable and positioned above the magnet. The upper plate part has a projection extending downward from an inner edge portion or an outer edge portion of the upper surface portion. The movable part comprises, as coils, a first coil and a second coil.The winding sections of the first coil and the second coil in the moving part are opposite a projection-side side surface, which is a side surface on the side of the upper plate part on which the projection is formed.

A system comprises an ear-worn electronic device configured to be worn by a wearer. The ear-worn electronic device comprises a processor and memory coupled to the processor. The memory is configured to store an annoying sound dictionary representative of a plurality of annoying sounds pre-identified by the wearer. A microphone is coupled to the processor and configured to monitor an acoustic environment of the wearer. A speaker or a receiver is coupled to the processor. The processor is configured to identify different background noises present in the acoustic environment, determine which of the background noises correspond to one or more of the plurality of annoying sounds, and attenuate the one or more annoying sounds in an output signal provided to the speaker or receiver.

A voice controlled assistant has a housing to hold one or more microphones, one or more speakers, and various computing components. The housing has an elongated cylindrical body extending along a center axis between a base end and a top end. The microphone(s) are mounted in the top end and the speaker(s) are mounted proximal to the base end. The microphone(s) and speaker(s) are coaxially aligned along the center axis. The speaker(s) are oriented to output sound directionally toward the base end and opposite to the microphone(s) in the top end. The sound may then be redirected in a radial outward direction from the center axis at the base end so that the sound is output symmetric to, and equidistance from, the microphone(s).

This application discloses a control method and an electronic device. The electronic device generates vibration when performing at least one function. The electronic device includes an acceleration sensor and a feedback circuit. The acceleration sensor is configured to output acceleration data, and the feedback circuit is configured to collect and feed back data related to the vibration. The electronic device obtains, based on a variation of a magnitude of the obtained acceleration data and interference data, a variation obtained after data processing, and performs action recognition. The electronic device performs a corresponding function based on a recognition result, or controls a second electronic device to perform a corresponding function. In this application, time consumption for searching for and locating a corresponding button can be shortened, and operation flexibility can be improved. In addition, when performing a function, the electronic device can accurately recognize another function to be used by the user, and eliminate interference between two or more functions.

An aircraft recorder system is provided in which a vibration sensor including at least one of a micro-electromechanical systems (MEMS) microphone and a MEMS accelerometer. The system further includes a cockpit voice recorder (CVR) and an active microphone. The active microphone and the vibration sensor each output signals to a signal processor including a subtractor configured to output, to the CVR, a signal that is a result of a subtraction of the signal from the vibration sensor from the signal from the active microphone.

To improve efficiency η of the entire acoustic device including an amplifier over the entire frequency band including a minimum resonance frequency F0.SOLUTION: An acoustic device 10 includes: a class D amplifier 1; and a speaker system SS comprising a voice coil to be driven by the class D amplifier 1. The class D amplifier 1 comprises a current feedback circuit 200. The speaker system SS has a Q value lower than the lower limit value of a proper range. The current feedback circuit 200 increases the acoustic device 10's Q value to a value in the proper range by increasing output resistance of the class D amplifier via feedback of current flowing through the voice coil to an input unit of the class D amplifier 1.SELECTED DRAWING: Figure 1

In examples, a device includes audio amplifier circuitry having an input and an output. The output is configured to couple to a speaker. The device also includes sense circuitry coupled to the output and configured to sense a voltage and a current of an analog audio signal from the audio amplifier circuitry. The current indicates a back electromotive force (EMF) of the speaker. The device also includes processing circuitry coupled to the sense circuitry, which is configured to calculate an impedance of a speaker based on the voltage and the current, compare the impedance to a target impedance, and indicate an operational status of the speaker responsive to the comparison.

Techniques are provided for generating sound using a speaker mounted to an enclosure (e.g., speaker cabinet) wherein a gas pressure level (e.g., air pressure level) inside the enclosure is lower than an ambient air pressure level outside the enclosure. The reduced gas pressure level within the enclosure provides an environment with a reduced pressure level at a back side of a speaker cone of the speaker, which enhances a low frequency response for a given speaker size, while also minimizing resonant frequencies and phase cancellation issues which could otherwise occur with conventional speaker systems in which acoustic sound waves are generated at the back side of the speaker cone. A pressure compensation system is utilized counteract a force applied to the front side of the speaker cone as a result of the gas pressure level inside the enclosure being lower than the ambient air pressure level outside the enclosure.

Acoustic transducer systems and methods of operating acoustic transducer systems are provided. The methods can involve: receiving an input audio signal; determining a position of a diaphragm; determining a correction factor, a motor force factor, a spring error factor, and a system spring factor based at least on the position of the diaphragm; determining a corrected voice coil current based at least on the input audio signal, the correction factor, the spring error factor, and a velocity of the diaphragm; and applying a corrected audio signal to a voice coil fixed to the diaphragm based at least on the corrected voice coil current, wherein the corrected audio signal corrects the input audio signal to compensate for non-linear characteristics of the acoustic transducer system.

An amplifier circuit for a microphone, a microphone circuit and an electronic device are provided. The amplifier circuit includes a first transistor having a gate serving as an input terminal of the amplifier circuit, a source serving as an output terminal of the amplifier circuit and a drain connected to ground, a first constant current source having an input terminal connected to a power supply and an output terminal connected to the source of the first transistor, and a source follower including at least a second transistor, having a drain connected to the power supply, a gate connected to the source of the first transistor and a source connected to the drain of the first transistor.

In an active noise reducing headphone, a signal processor applies filters and control gains of both the feed-forward and feedback active noise cancellation signal paths. The signal processor is configured to apply first feed-forward filters to the feed-forward signal path and apply first feedback filters to the feedback signal path during a first operating mode providing effective cancellation of ambient sound, to apply second feed-forward filters to the feed-forward signal path during a second operating mode providing active hear-through of ambient sounds with ambient naturalness, and to apply third feed-forward filters to the feed-forward signal path during a third operating mode providing active hear-through of ambient sounds with a different total response than is provided in the second operating mode.

A work machine includes a lower traveling body; an upper rotating body mounted on the lower traveling body so as to be freely rotatable; a traveling space provided in the upper rotating body; an external sound collecting device disposed outside the traveling space; an internal sound outputting device disposed inside the traveling space; and a control device configured to limit the output of sound collected by the external sound collecting device from the internal sound outputting device according to a detection result of an object existing around the work machine.

A magnetic angle sensor outputs a component Vs in a Y direction where a vibration system of a synthetic vector of a magnetic vector of a magnetic circuit of a speaker and a magnetic vector of a displacement detection magnet fixed on the vibration system and a component Vc in an X direction orthogonal to the Y direction. A test signal is applied to the speaker, and collection of (Vs, Vc) and a measurement of a Y-direction displacement of the vibration system by a displacement meter are performed. A conversion equation "z=alxVs+a2xVc" for the first principle component is obtained by principle component analysis on collected (Vs, Vc), and a conversion equation "y=blxz2+b2xz+b3" for conversion to a displacement y is obtained by polynomial regression on the Y-direction displacement y of the displacement detection magnet obtained from a measurement value of the displacement meter and z calculated from collected (Vs, Vc).

To provide a "speaker over-amplification suppression device" that more precisely controls the amplitude of the speaker's vibration system to a targeted amplitude range.SOLUTION: An amplitude control unit 6 adjusts the gain of a sound source output signal output by a sound source device 5 and outputs it to an amplifier 4 that drives a speaker 2. The amplitude control unit 6 corrects the displacement of the speaker 2 predicted from the sound source output signal on the basis of the equivalent circuit of the speaker 2 by using an actual value during a past period of the difference between the predicted displacement of the speaker 2 and the displacement of the vibration system of the speaker 2 detected by the displacement detection unit 7 using the sensor 3, and adjusts the gain of the sound source output signal such that the corrected displacement does not exceed a target displacement width.SELECTED DRAWING: Figure 1

An apparatus for processing an audio input signal having one or more audio input channels to obtain an audio output signal having one or more audio output channels has an estimation unit configured to estimate a radiation resistance of each driver of one or more drivers of each loudspeaker of one or more loudspeakers as an estimated radiation resistance; or as an estimated radiation impedance, wherein said estimated radiation impedance has estimated information on the radiation resistance of said driver; and a processing unit configured to obtain the audio output channels by processing each audio input channel depending on the estimated radiation resistance or the estimated radiation impedance of each driver of each loudspeaker. The estimation unit is configured to estimate the estimated radiation resistance or the estimated radiation impedance depending on estimated sound pressure information indicating an estimation of sound pressure at said driver of said loudspeaker, and depending on estimated velocity information indicating an estimation of a driver velocity of said driver of said loudspeaker.

To provide a limiter system and method for avoiding clipping distortion or increasing the maximum sound level of an active speaker.SOLUTION: The present disclosure provides a limiter system. The limiter system includes a first equalization filter, a low-pass filter, a first limiter, a high-pass filter, a second limiter, and a mixer. The limiter system provided by the present disclosure further includes a second equalization filter. An audio signal from a signal source first passes through the first equalization filter, the equalized signal is divided into two signals first, one signal is processed by the low-pass filter and the first limiter, the other signal is processed by the high-pass filter and the second limiter, and then the two processed signals enter the mixer to be mixed and outputted. The mixed output signal is subjected to second equalization filtering by the second equalization filter to avoid clipping distortion or to obtain a higher maximum sound level.SELECTED DRAWING: Figure 1