390results about "Amplifiers" patented technology

A mechanism is provided for automatically controlling the operation of a media device based at least in part upon whether a portable presentation device coupled to the media device is currently being worn by a user. A portable presentation device may be any device that is meant to be worn by a user and that is capable of presenting media content to the user (e.g. earphones, headphones, goggles or faceplates with video/audio capability, etc.). With this mechanism, a user can affect the operation of the media device by simply putting on or taking off the portable presentation device. The user does not need to manually manipulate the controls of the media device. By automatically controlling the operation of the media device in this manner, use of the media device and the portable presentation device as a unit is made much simpler and more convenient.

According to some embodiments of the present invention, an impedance transformation circuit is provided for use with a transmitter, a receiver, and an antenna. The transmitter may provide transmission signals for transmission by the antenna. The antenna may provide received signals having an associated signal parameter to the receiver. The impedance transformation circuit includes an impedance adjusting circuit and a controller. The impedance adjusting circuit is connected between the antenna, the receiver, and the transmitter. The impedance adjusting circuit is configured to change an impedance difference presented between at least one of: 1) the transmitter and the antenna, and 2) the antenna and the receiver, in response to a control signal. The controller generates the control signal to change the presented impedance difference in response to a signal parameter.

A computer readable memory to direct a computer to improve the perceived audio quality of a speaker included in that computer. The computer readable memory stores a first, second and third set of instructions. The first set of instructions causes the computer to determine the speaker type. The second set of instructions causes the computer to select a set of default filter coefficients for a digital filter based upon the speaker type. Finally, the third set of instructions causes the computer to realize a digital parametric equalizer using a digital filter and the set of default filter coefficients. Thus, the digital filter alters the audio signal that is input to the speaker, thereby improving the perceived quality of the speaker.

A speaker system for a musical instrument that detects the displacement of a voice coil of a speaker and provides feedback processing. The speaker system has a preamp that alters the frequency characteristics of the an electrical signal that has been input to an input terminal, and a power amplifier that amplifies the electrical signal. A speaker is driven by the power amplifier and a feedback unit detects the displacement of the speaker and provides a feedback signal to the power amplifier. The power amplifier amplifies the electrical signal in conformance with the output of the preamp and the feedback signal.

An earpiece for providing an audio signal to two ears of a user, includes an audio interface for providing the audio signal, a bone conduction speaker coupled to the audio interface for outputting an output signal, an adaptive filter with an adjustable impulse response to provide a filtered signal that once played to the second ear of a user, by an in-ear speaker, reduces an audio effect of the leakage signal on the second ear of the user, an in-ear speaker coupled to the audio interface for providing an in-ear audio signal to the second ear of the user, in response to the filtered signal and the second input signal, an in-ear microphone for sensing a sensed audio signal, and a processor for updating an impulse response of the adaptive filter in order to reduce a contribution of the leakage signal to the sensed audio signal.

A method of amplification includes amplifying an input signal with a predetermined or user adjustable maximum gain to produce a second signal and compressing the dynamic range of the second signal with an automatic gain control to produce an output signal. The compression ratio of the automatic gain control is greater than one for output signals below a predetermined threshold output signal level and is essentially one for output signals above the predetermined threshold output signal level. The compression ratio may be predetermined or the method may include determining the compression ratio of the automatic gain control. The compression ratio may be determined according to the amplitude of the output signal or according to an input-output curve. The input-output curve my be predetermined and may be selected according to the auditory needs of a listener. Preferably the input-output curve is determined according to the predetermined or user adjustable maximum gain.

A computer system having automatic speaker detection circuitry is disclosed. The typical computer system includes a central processing unit, a data input device, and a sound card. Further, there is an audio amplifier, as well as an automatic detection and selection circuit that may be within the sound card or the audio amplifier or just part of the computer system as a whole. This automatic detection selection device is able to determine an impedance load of an output device attached to the computer system, namely, a speaker system, and is able to disable the audio amplifier within the computer system upon determining the impedance load and matching that impedance load against a selected value indicating that no amplification of the signal is required for the output device. Further, an audio sound equalizer is part of the system and can be bypassed in the same manner that the audio amplifier is, namely, that particular impedance load is measured indicating that no equalization is necessary.

A digital audio system including a combination of analog and digital volume control is disclosed. A variable power supply voltage biases a power amplifier for each channel, and applies a bias voltage corresponding to an analog volume control signal. In one disclosed embodiment, digital gain control circuitry compares the bias voltage with the level expected for the analog volume control signal; if the bias voltage has not dropped in response to a reduction in the analog volume control signal, the digital gain control circuitry reduces the digital gain of the input digital audio signal, until the bias voltage responds to the reduced volume. In another disclosed embodiment, modeling or characterization of the audio system is used to derive a digital gain control signal based on the desired volume signal and the amplitude of the digital audio signal itself. In another disclosed embodiment, a slew rate limiter slows the rate of change of the control signal applied to the variable power supply, in which case the slowed control signal is used in the comparison or calculations of the reduced digital gain.

A method and apparatus for identifying running vehicles in an area to be monitored using acoustic signature recognition. The apparatus includes an input sensor for capturing an acoustic waveform produced by a vehicle source, and a processing system. The waveform is digitized and divided into frames. Each frame is filtered into a plurality of gammatone filtered signals. At least one spectral feature vector is computed for each frame. The vectors are integrated across a plurality of frames to create a spectro-temporal representation of the vehicle waveform. In a training mode, values from the spectro-temporal representation are used as inputs to a Nonlinear Hebbian learning function to extract acoustic signatures and synaptic weights. In an active mode, the synaptic weights and acoustic signatures are used as patterns in a supervised associative network to identify whether a vehicle is present in the area to be monitored. In response to a vehicle being present, the class of vehicle is identified. Results may be provided to a central computer.

A biasing circuit for an acoustic transducer is provided with: a voltage-booster stage, which supplies, on a biasing terminal, a boosted voltage for biasing a first terminal of the acoustic transducer; and filtering elements, set between the biasing terminal and the acoustic transducer, for filtering disturbances on the boosted voltage. The biasing circuit is further provided with switches, which can be actuated so as to connect the first terminal to the biasing terminal of the voltage-booster stage, directly during a start-up step of the biasing circuit, and through the filtering elements at the end of the start-up step.

A portable electrical appliance comprises an audio signal source, a power supply module having a housing external to the portable electrical appliance for providing power to the electronic appliance having, a power converter for providing DC power to at least the portable electrical appliance, a speaker for generating sound and audio processing means for manipulating audio signals from the audio signal source, wherein the power converter, audio processing means and speaker are mounted within the housing, and communication means for coupling the audio signal to the processing means. The communication means is able to be wireless or wired.

The present invention provides a vertically or horizontally placeable combinative array speaker. The vertically or horizontally placeable combinative array speaker includes a microprocessor, an orientation sensor coupled to the microprocessor to sense condition changes of the combinative array speaker, a sound field reconstructing unit formed within or outside of the combinative array speaker, wherein the sound field reconstructing unit is coupled to the microprocessor to simulate surround sounds, and array speakers coupled to the sound field reconstructing unit through an amplifier.

Disclosed is a method for maintaining and/or improving skin health in the area of a wearer covered by an absorbent article. The absorbent article includes a vapor permeable backsheet, a liquid pervious topsheet positioned in facing relation with the backsheet, an absorbent core located between the backsheet and the topsheet. The absorbent article also includes skin care compositions thereon for maintaining and/or improving skin health.

A headset used as an external louder speaker and a method for adjusting an output of the speaker transducers are disclosed. The headset includes a signal receiver, speaker parts, hinge parts, and amplifiers. The speaker parts change their direction through the hinge parts. The output of speaker transducers is adjusted according to the direction of the speaker parts. When the output of speaker transducers is increased, the speaker parts of the headset are used as an external speaker.

Embodiments of amplifiers and electrodes for capacitive styluses are disclosed. The amplifiers detect an input signal from a capacitive touch sensor, such as a touchscreen or touchpad, amplify and invert the signal, and emit the amplified and inverted signal to cause the capacitive touch sensor to detect a touch. The electrode sets, or tips, pair a sensing electrode and an emitting electrode, shielded from each other to limit interference, in a fine-point non-deforming configuration that improves usability over existing stylus tips.

The invention relates to a sound-emitting device with controllable directivity comprising a plurality of sound sources (7) distributed over the surface of a body 5, each of said sound sources (7) being driven by a separate power amplifier (12), the input terminal of which is provided with the output signal from a corresponding filter (10), such that the frequency response of each individual sound source (7) can be controlled, where each filter (10) is provided with an input signal (11) corresponding to a plurality of input channels Ch₁, Ch₂ . . . Ch_N. The body (5) could according to one embodiment of the invention comprise a cylindrical body provided with end pieces (6) at either longitudinal end. The present invention furthermore relates to a method for controlling the individual sound sources of the sound-emitting device in order to obtain a given target directivity.

A digital/analog conversion apparatus for converting a digital signal into an analog signal. The digital/analog conversion apparatus can generate a high-quality analog signal, even when elements configuring the digital/analog conversion apparatus have variance, with high resolution and a small circuit size. The data conversion apparatus is provided with a first data converter for reducing the number of bits of an input signal, a second data converter for converting the format of the first output signal, and a third data converter for conversion into a code which corresponds to the history of the output from the second data converter.

A power conversion apparatus, such as a UPS, includes a first waveform reference signal generator circuit operative to generate a first waveform reference signal responsive to an AC bus, and a second waveform reference signal generator circuit operative to generate a second waveform reference signal, e.g., a more consistently sinusoidal signal produced by another source. The apparatus further includes a control circuit that selectively generates a third waveform reference signal from the first and second waveform reference signals, and a power converter circuit (e.g., a rectifier and/or inverter) coupled to the AC bus and operative to transfer power to and/or from the AC bus responsive to the third waveform reference signal. In particular, the control circuit may be operative to weightedly combine the first and second waveform reference signals to generate the third waveform reference signal. The control circuit may weightedly combine the first and second waveform reference signals responsive to an operating parameter of the power converter, such as a voltage, a current, a power factor, a source impedance, a voltage distortion and/or a harmonic input current.

There is provided a multichannel audio amplification apparatus including a speaker detection circuit for detecting whether or not a speaker is connected to an arbitrary speaker terminal of speaker terminal groups TA and TB, and an operating circuit and a display circuit connected to a control circuit. Even in a case where one of two speaker groups of A and B types connected to the multichannel audio amplification apparatus cannot be connected with a surround speaker for reproducing only a surround sound, a listener is prevented, by indication, from carrying out on the operating circuit an erroneous operation or setting which otherwise might be liable to occur both in a case where the B-type speaker group including no surround speaker is connected to the multichannel audio amplification apparatus and in a case where the B-type speaker group is not connected thereto.

A computerized wagering game system has a gaming module comprising a processor and gaming code which is operable when executed on the processor to conduct a wagering game on which monetary value can be wagered, and an audio module comprising a digital audio amplifier, the audio module operable to receive digital audio signals and to amplify them to produce an amplified digital audio signal. In some embodiments, the digital amplifier produces a pulse width modulated amplified digital audio signal, which is in further embodiments also pulse frequency modulated.

A band-splitting time compensation signal processing device 2 includes a band-splitting circuit 211 for extracting, after extracting a signal of a high-frequency band component or low-frequency band component from an input signal, a signal of the low-frequency band component or high-frequency band component by subtracting the signal of the high-frequency band component or low-frequency band component from the input signal; a delay circuit 212 for delaying, for adjusting arrival time, at least one of the high-frequency band component and low-frequency band component output from the band-splitting circuit 211; and a mixing circuit 213 for combining the high-frequency band component or low-frequency band component output from the delay circuit 212 with the low-frequency band component or high-frequency band component output from the band-splitting circuit 211.