Abstract: An apparatus for generating a drive signal for a sound transducer (109) comprises a sound generator (101) which provides an input audio signal. A divider (101) divides the input audio signal into at least a low frequency signal and a high frequency signal and an expander (105) generates an expanded signal by applying a dynamic range expansion to the low frequency signal. A combiner (107) then generates the drive signal by combining the expanded signal and the higher frequency signal. The threshold for applying the dynamic range extension may be adjusted depending on the amplitude of the low frequency signal. The low frequency signal may furthermore be compressed into a narrow frequency band around a resonance frequency. The approach may allow improved audio quality especially from high Q low frequency sound transducers by attenuating decay parts of bass signals thereby reducing sustain or ringing for bass notes.

Abstract: A channel divider that can suitably set a crossover frequency when a biwiring-connectable multiway speaker system including network circuits are used is provided. The channel divider includes a low-pass filter LPF and a high-pass filter HPF for dividing a band of a sound signal into a first output signal and a second output signal so as to output the signals, and a control circuit for controlling the filters. The channel divider has a sound output mode in which the control circuit sets a cutoff frequency fcL of LPF to a value higher than fc0 by about ? to 1 Oct., sets a cutoff frequency fcH of HPF to a value lower than fc0 by about ? to 1 Oct., and outputs the first output signal and the second output signal including frequency bands fcL to fcH when any crossover frequency fc0 for defining the band division is specified.

Abstract: A process and system for enhancing and customizing sound comprises receiving an input audio sound and processing the input by one or more filter blocks to dynamically reshape the dynamic, phase and frequency content of the input audio sound. The parallel processed audio is combined in a sound mixer and tube harmonics are added to the output from the mixer. The tube harmonics added audio is fed to a highpass filter which sets a frequency limit of audio passing through this block. A low pass filter movines the audio in a plus or minus direction with a dynamic envelope control. A frequency divider is provided for shifting audio sound below a selected frequency down an octave. Output from this stage is edited by feeding a certain amount of each side of the audio to a corresponding opposite side. The frequency balance is adjusted by setting a band phase coherent equalizer for frequency adjustments. The original, unprocessed sound is then mixed with the processed audio.

Abstract: A speaker that includes a pair of spaced-apart, in-plane mounted drivers connected in series to a network for applying the appropriate frequency component of the electrical input drive signal to each of the drivers is disclosed. A frequency dependent shunting network, such as a low pass filter, is applied to one of the drivers so as to gradually mute the one driver as a desired frequency is approached. The result is an aesthetically pleasing speaker that has dual in-plane drivers and that produces superior sound quality throughout the entire frequency range of the speaker, including those ranges in which dual, in plane, drivers tend to acoustically interfere with each other.

Abstract: A canalphone system may include a canalphone housing, and a first high frequency driver carried within the canalphone housing. The system may also include a second high frequency driver carried within the canalphone housing where the second high frequency driver is tuned with the first high frequency driver to deliver lower distortion than a standard canalphone high frequency driver and/or lower distortion than two standard canalphone high frequency drivers that are not tuned with each other.

Abstract: Integrated processing of multimedia signals can eliminate unnecessary signal processors and converters without losing the functionality of typical home entertainment system components. The integrated multimedia system includes a main player that captures and processes signals digitally. The main player may adjust the audio signal to provide audio output of equal loudness across all frequencies by accounting for sensitivity of the human ear for sounds of varying frequencies. The main player can also account for perceived differences in loudness based on the angle of a listener to a speaker by detecting the position of a user and making an adjustment accordingly. The invention further provides a speaker that has embedded performance characteristics or an identifier that allows the system to provide an optimal speaker driving current for a particular system or determine how that speaker would be best implemented in the integrated system.

Abstract: A speaker arrangement comprises a first sound transducer (101) for reproducing sound in a lower frequency range and having a first on-axis direction and a first center point. The arrangement further comprises a second sound transducer (103) for reproducing sound in a higher frequency range, the second sound transducer (103) being mounted in front of the first sound transducer and having a second on-axis direction and a second center point. The transducers are positioned such that an angle between the first on-axis direction and the second on-axis direction is between 45° and 135°, and such that the distance between the first center point and the second center point is not higher than a cross-over wavelength corresponding to the cross-over frequency. The cross-over frequency between the lower frequency range and the higher frequency range is selected to be within the interval from 1.5 kHz to 3 kHz. An improved point source approximation may be achieved.

Abstract: A signal processing device for supplying sound signals to a first speaker for emitting a sound on a low-pitched sound side and a second speaker for emitting a sound on a high-pitched sound side higher than the low-pitched sound side, includes a control portion that controls a characteristic of the sound signal supplied to the first speaker so that an output level of the first speaker is maintained at a crossover frequency between the first speaker and the second speaker, when an output level of the sound signal supplied to the first speaker is changed.

Abstract: The present invention discloses a driving circuit for electronic horn and a driving method for the electronic horn. The driving circuit includes an oscillating circuit, which generates a signal having oscillating frequency. Based on the signal, said driving circuit generates a driving signal to drive the electronic horn to produce sound. It is characterized in that said oscillating circuit includes a variable capacitor, and the oscillating frequency is changed by adjusting capacitance of the variable capacitor so as for the frequency of the driving signal to be consistent with working frequency of the electronic horn. The present invention overcomes the problem of mismatch between the frequency of circuit's driving signal and the horn's sounding diaphragm and horn's tone inflexion due to resistance change caused by vehicle vibration.

Abstract: Apparatus for reproducing sound including at least three loudspeakers (5, 6, 7) mounted in a substantially sealed enclosure. The three loudspeakers may be mounted to a wall of the enclosure so that they are all directed away from, and evenly spaced around, a common point. Two speakers may be driven with the respective out of phase signals comprising the difference between two stereo channels and another speaker with the sum of those channels.

Abstract: Frequency response correction systems and methods for consumer electronic (CE) devices are disclosed. Applying one or more of disclosed techniques can improve a consumer's listening experience. The frequency response of a CE device can be corrected to remove or attenuate salient, undesirable features of with minimal user interaction. Audio quality can be tuned for optimal or near optimal performance even at maximum or near maximum volume levels substantially without fluctuations, clipping, or any other distortions. In some embodiments, audio response of the CE device can be captured, smoothed, and corrected. Correction parameters can be stored on the CE device.

Abstract: A reproducing apparatus includes: a digital signal processing block configured to execute first boost processing for setting a volume level for an entered digital audio signal and boosting an amplitude level of the signal; a digital-to-analog conversion block configured to convert the digital audio signal into an analog one; an analog signal processing block configured to execute second boost processing for boosting an amplitude level of the analog audio signal; an analog volume adjusting block configured to set a volume level for the analog audio signal from the analog signal processing block; a loudspeaker configured to output the analog audio signal from the analog volume adjusting block; an operating block configured to indicate a volume level of an audio signal from the loudspeaker and turn on/off the boost processing for the audio signals; and a control block configured to control components in accordance with an operation by the operating block.

Abstract: Methods and systems are provided for adjusting a crossover frequency between a plurality of audio speakers rendering audio content. In one example, a first subset of a plurality of audio speakers may be rendering a first sub-range of a range of audio frequencies of an audio content, and a second subset of speakers of the plurality of audio speakers may be rendering a second sub-range of the range of audio frequencies. In this example, the first sub-range and the second sub-range may be substantially separated at the crossover frequency. In one case, a playback volume at which the audio content is being rendered may be adjusted. In one instance, the crossover frequency may be adjusted in response to the volume adjustment to improve the audio content rendering quality by the respective subsets of audio speakers in the plurality of audio speakers.

Abstract: A spectral management system may be used in an audio system to receive and process audio signals having multiple distributed audio channels, such as a right, left, center, right side, left side, right rear and left rear channels. The spectral management system may separate and route a frequency range of audio content included in one or more of the distributed audio channels to other distributed audio channels. The separated and routed frequency range of audio content may be combined with audio content present on the other distributed audio channels to which the separated frequency range of audio content is routed. Separation, routing and combination may include bass audio content routing, mid-bass audio content routing, subwoofer audio content routing and treble audio content routing.

Abstract: A front surround sound reproduction system which improves the performance of beam steering by using a speaker array arranged geometrically on two or more planes or on one curved surface, and a signal reproducing method of the system. The audio reproduction apparatus to reproduce a multi-channel audio signal by using a plurality of speakers includes a signal distribution unit to duplicate a multi-channel audio signal and to distribute the duplicated signals as one or more groups of multi-channel signals corresponding to one or more speaker array groups, a steering processing unit to form sound beams with steering angles predetermined in relation to each speaker array group, from the groups of multi-channel signals distributed by the signal distribution unit, and a speaker array unit having one or more speaker array groups to reproduce the sound beams of each group formed by the steering processing unit, in the speaker array group.

Abstract: A passive loudspeaker multiplexer (1) adapted to be interconnected between an amplifier (2) and a plurality of loudspeakers (24-32), includes two input ports (4, 6) adapted to be connected to the output ports (2a, 2b) of an amplifier (2); two output ports (20, 22) adapted to be connected to the input ports of a plurality of loudspeakers (24-32) such that the plurality of loudspeakers are connected in parallel to the output ports; at least one first capacitor (8, 10) connected between a first input port (4) and a first output port (20); a first high pass (16, 18) connected between the output ports.

Abstract: A computer-implemented method and system are provided for profiling or analyzing audio data based on an audio parameter. The audio data is divided into audio data into segments. Each segment is characterized by the audio parameter in a defined range. Effects are selected according to the segments meeting criteria for the audio parameter of the effects. A media presentation is authored or generated using the selected effects.

Abstract: An audio system including a rendering processor for separately rendering a dialogue channel and a center music channel. The audio system may include circuitry for extracting one or both of the dialogue channel or the center music channel from program material that does not include both a dialogue channel and a center music channel. The dialogue channel and the center music channel may be radiated with different radiation patterns.

Abstract: A method and apparatus to enhance one or more low-frequency components and one or more medium-frequency components of an audio signal. The method includes performing filtering on the input audio signal using a plurality of band-pass filters, generating a plurality of harmonic-frequency signals using a plurality of audio signals resulting from the performing filtering operation, and mixing the plurality of harmonic-frequency signals with the input audio signal.

Abstract: An instrument amplification system provides improved low frequency enhancement. A powered subwoofer system enhances the low frequency components of a standard instrument amplifier by incorporating a speaker level high-pass filter crossover network prior to connection to a standard instrument speaker. The speaker level instrument amplifier output is also attenuated, low-pass filtered and re-amplified to drive a dedicated low frequency subwoofer speaker. In one embodiment, a single speaker cabinet connects via a single speaker cable and includes both typical instrument speakers and an active powered subwoofer system. In another embodiment, a stand alone active powered subwoofer connects to a standard instrument amplifier and includes a speaker level high-pass crossover output for connection to a standard instrument speaker cabinet. The instrument amplifier speaker output is attenuated, low-pass filtered, re-amplified and connected to a low frequency subwoofer speaker.

Abstract: An automated audio tuning system may optimize an audio system for power efficiency when performing automated tuning of the audio system to optimize acoustic performance. The system may establish any number of different power efficiency weighting factors to provide a balance between acoustic performance and power efficiency during operation. The power efficiency weighting factors may range from representing optimizing power efficiency with constrained optimization of acoustic performance to optimized acoustic performance with minimized regard for power efficiency. For each of the efficiency weighting factors, the system may generate operational parameters, such as filter parameters, to achieve a target acoustic response while maintaining a determined level of power efficiency.

Abstract: A gaming machine for conducting a wagering game includes selective application of surround sound. The selective application of surround sound allows certain key gaming events to be emphasized over other gaming events. The surround sound may be varied to produce certain effects, such as a tactile effect and a gradual building up of suspense and anticipation that increases player excitement and enjoyment. A surround sound decoder may be added in some embodiments to convert monophonic and stereo wagering games into surround sound. The surround sound may be implemented as true surround sound or as virtual surround sound.

Abstract: A method of communicating with an ingestible capsule includes detecting the location of the ingestible capsule, focusing a multi-sensor acoustic array on the ingestible capsule, and communicating an acoustic information exchange with the ingestible capsule via the multi-sensor acoustic array. The ingestible capsule includes a sensor that receives a stimulus inside the gastrointestinal tract of an animal, a bidirectional acoustic information communications module that transmits an acoustic information signal containing information from the sensor, and an acoustically transmissive encapsulation that substantially encloses the sensor and communications module, wherein the acoustically transmissive encapsulation is of ingestible size. The multi-sensor array includes a plurality of acoustic transducers that receive an acoustic signal from a movable device, and a plurality of delays, wherein each delay is coupled to a corresponding acoustic transducer.

Abstract: A system includes a plurality of inputs each configured to receive a filtered version of a source signal. The system extracts the energy information from each input signal and compares the energy information of a plurality of input signals. Alternatively, the system extracts energy information from a signal that is the difference of two input signals. Based on the energy information, the system determines at least one parameter that may be changed in at least one circuit in a plurality of circuits to minimize the differences in energy of the input signals or to minimize the energy of the difference signal. Parameters may include for example amplification, delay, and corner frequency values. The set of circuits may include microphone interface circuits. Merely by way of example, a system with microphone interface circuits may be included in a hearing enhancement device or in a hands-free earpiece.

Abstract: An apparatus comprising: at least one filter configured to filter an electrical input signal and provide a filtered electrical input signal to at least one speaker module configured to convert the filtered electrical input signal to an acoustic signal; and a detector configured to receive the filtered electrical input signal as a first input and an electrical output signal provided by at least one microphone as a second input; wherein the detector is configured to determine at least one difference between the electrical output signal provided by the at least one microphone and the filtered electrical input signal provided to said speaker module and, in response to the at least one difference provide a control signal to the filter to control the filter.

Abstract: A system and method for an audio system with two or more speakers, drivers, sources and the like is presented. An audio system includes a first speaker that reproduces sounds in a first frequency range and a second speaker that reproduces sounds in second frequency range. A crossover frequency is formed between the first frequency range and the second frequency range. The first speaker and the second speaker are physically separated by more than one wavelength of the crossover frequency and the first speaker is arranged horizontal with respect to the second speaker.

Abstract: The invention provides an efficient implementation of cross-product enhanced high-frequency reconstruction (HFR), wherein a new component at frequency Q?+?q is generated on the basis of existing components at ? and Q?+?q. The invention provides a block-based harmonic transposition, wherein a time block of complex subband samples is processed with a common phase modification. Superposition of several modified samples has the net effect of limiting undesirable intermodulation products, thereby enabling a coarser frequency resolution and/or lower degree of oversampling to be used. In one embodiment, the invention further includes a window function suitable for use with block-based cross-product enhanced HFR. A hardware embodiment of the invention may include an analysis filter bank (101), a subband processing unit (102) configurable by control data (104) and a synthesis filter bank (103).

Abstract: A front surround reproduction system improving the stereo effect of mid and low frequency signals by using a psychoacoustic model, and a method thereof.

Abstract: A channel divider that can suitably set a crossover frequency when a biwiring-connectable multiway speaker system including network circuits are used is provided. The channel divider includes a low-pass filter LPF and a high-pass filter HPF for dividing a band of a sound signal into a first output signal and a second output signal so as to output the signals, and a control circuit for controlling the filters. The channel divider has a sound output mode in which the control circuit sets a cutoff frequency fcL of LPF to a value higher than fc0 by about ? to 1 Oct., sets a cutoff frequency fcH of HPF to a value lower than fc0 by about ? to 1 Oct., and outputs the first output signal and the second output signal including frequency bands fcL to fcH when any crossover frequency fc0 for defining the band division is specified.

Abstract: The present invention provides for methods and systems for digitally processing an audio signal. Specifically, the present invention provides for a speaker system that is configured to digitally process an audio signal in a manner such that studio-quality sound that can be reproduced.

Abstract: Implementations related to echo cancellation are depicted and described herein.

Abstract: Widening stereophonic response is achieved in sound reproduction systems with at least two loudspeakers. A stereo signal input is accessed, which includes multiple frequency components. The loudspeakers are close to each other. A frequency range of the frequency components is decorrelated, e.g., upon pre-processing the stereo signal. The sound reproduction system's stereophonic response is widened, based on the decorrelation.

Abstract: An array speaker apparatus SParray includes a first radiation means for driving speaker units so that a first sound S1 of a main channel is radiated to a wall surface W1 on the left or right side of a listening position, and a second radiation means for driving the speaker units so that a second sound S2 the same as the first audio signal is radiated directly to the listening position.

Abstract: A system and method provide at least a single stage optimization process which maximizes the flatness of the net subwoofer and satellite speaker response in and around a cross-over region. A first stage determines an optimal cross-over frequency by minimizing an objective function in a region around the cross-over frequency. Such objective function measures the variation of the magnitude response in the cross-over region. An optional second stage applies all-pass filtering to reduce incoherent addition of signals from different speakers in the cross-over region. The all-pass filters are preferably included in signal processing for the satellite speakers, and provide a frequency dependent phase adjustment to reduce incoherency between the center and left and right speakers and the subwoofer. The all-pass filters are derived using a recursive adaptive algorithm.

Abstract: 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.

Abstract: A front surround sound reproduction system using a speaker array, a front surround sound reproduction system to perform stereo localization using a beam forming speaker array, and a surround sound reproduction method thereof. A front surround sound reproduction apparatus using a plurality of speakers includes a first signal processing unit to adjust a frequency characteristic of each first and second channel signal and to output the adjusted signals to left and right speakers assigned according to a frequency band, a second signal processing unit to generate a plurality of channel signals by copying the first and second channel signals, to adjust a signal characteristic of each of the plurality of channel signals, and to output the adjusted signals to a speaker array in the center, and a speaker unit having a plurality of speakers to reproduce the signals output from the first signal processing unit and the second signal processing unit.

Abstract: The quality of music output from audio systems is improved by simulating the effect of low frequency signals in the human ear. This thus allows listeners to perceive the lower frequency signals, even though the speakers may be incapable of providing such low frequency outputs. Method and systems provided for processing enhancing bass effect in audio signals. Said method and systems result in the bass enhancement being computationally less intensive. The bass effect enhancement techniques described are based on the response of sine and cosine transfer functions and on the directional independence of low frequency components. The human ear is unable to resolve directions from low frequency components. The bass effect enhancement technique alternatively is based on response of an exponential transfer function.

Abstract: An audio signal processing apparatus includes a high-frequency components extraction means for extracting high-frequency components higher than a predetermined cutoff frequency from the input audio signal and supplying them to satellite speakers by way of a predetermined high frequency range amplifier, a low-frequency components extraction means for extracting low-frequency components lower than a predetermined cutoff frequency from the input audio signal, a correlation reducing means for reducing the correlation of the high-frequency components and the low-frequency components of the input audio signal and a delay means for delaying the low-frequency components and supplying them to a subwoofer by way of a predetermined low frequency range amplifier.

Abstract: Provided are a method and apparatus for audio bass enhancement using stereo speakers. By filtering a baseband signal of an input signal whose frequency is lower than a blocking frequency calculated based on the distance between first and second speakers, delaying the filtered signal for a predetermined time period, combining a signal component of the input signal output from the first speaker and a signal component of the delayed signal output from the first speaker and making the combined signal component correspond to the first speaker, and combining a signal component of the input signal output from the second speaker and a signal component of the delayed signal output from the second speaker and making the combined signal component correspond to the second speaker, deep and rich audio bass can be provided by a simple operation without structural modification of speakers with respect to micro speakers in which audio bass reproduction is not conventionally performed efficiently.

Abstract: The quality of music output from audio systems is improved by simulating the effect of low frequency signals in the human ear. This thus allows listeners to perceive the lower frequency signals, even though the speakers may be incapable of providing such low frequency outputs. A method is provided for processing enhancing bass effect in audio signals. The method also results in the bass enhancement being computationally less intensive. The bass effect enhancement techniques are based on the response of sine and cosine transfer functions and on the directional independence of low frequency components. The human ear is unable to resolve directions from low frequency components. The bass effect enhancement technique alternatively is based on the response of an exponential transfer function.

Abstract: The present invention provides methods and systems for digitally processing audio signals. Some embodiments receive an audio signal and converting it to a digital signal. The gain of the digital signal may be adjusted a first time, using a digital processing device located between a receiver and a driver circuit. The adjusted signal can be filtered with a first low shelf filter. The systems and methods may compress the filtered signal with a first compressor, process the signal with a graphic equalizer, and compress the processed signal with a second compressor. The gain of the compressed signal can be adjusted a second time. These may be done using the digital processing device. The signal may then be output through an amplifier and driver circuit to drive a personal audio listening device. In some embodiments, the systems and methods described herein may be part of the personal audio listening device.

Abstract: Separating a source in a stereo signal having a left channel and a right channel includes transforming the signal into a short-time transform domain; classifying portions of the signals having similar panning coefficients; segregating a selected one of the classified portions of the signals corresponding to the source; and reconstructing the source from the selected portions of the signals.

Abstract: A system is provided for configuring an audio system for a given space. The system may statistically analyze potential configurations of the audio system to configure the audio system. The potential configurations may include positions of the loudspeakers, numbers of loudspeakers, types of loudspeakers, listening positions, correction factors, filters, or any combination thereof. The statistical analysis may indicate at least one metric of the potential configuration including indicating consistency of predicted transfer functions, flatness of the predicted transfer functions, differences in overall sound pressure level from seat to seat for the predicted transfer functions, efficiency of the predicted transfer functions, or the output of predicted transfer functions.

Abstract: Integrated processing of audio/video signals can eliminate unnecessary signal processors and converters without losing the functionality of typical home entertainment system components. The integrated system includes a main player that captures and processes signals digitally, a dummy display, and a dummy speaker. The dummy display may only have a display panel and a panel driver. The dummy speaker may only have a driving unit and no crossover logic. The main player may have a PC architecture and process all signals digitally for outputting signals tailored for the display device and the individual driving units of the dummy speaker. The integrated system may also provide dynamic signal adjustments based on the surrounding environment. The main player may include a storage device and can process media content stored therein to produce supplemental information to provide an optimal audiovisual experience. This supplemental information can be shared among users over a network connection.

Abstract: An audio crossover system and method is disclosed. An audio system includes two driver circuits, one for each of two audio frequency ranges, e.g., high and low frequency ranges. The driver circuits are designed to provide a combined frequency response curve that has a pronounced midrange attenuation dip, in contrast to prior art designs that attempt to provide a flat response over all frequency ranges.

Abstract: A controller device is provided whereby players can experience realistic sounds. The controller device is connected to the main body of an information processing apparatus, wherein the controller device comprises a first speaker for emitting a sound signal in a low frequency range, and a second speaker for emitting a sound signal in a frequency range that is higher in comparison with the first speaker.

Abstract: A signal processing system includes a level dependent bass management system. The level dependent bass management system utilizes audio input signal level information to apply at least one of multiple, available bass management solutions to generate one or more output signals from the audio input signal. In at least one embodiment, initially the level dependent bass management system boosts components of the audio input signal in the low frequency range by an amount sufficient to at least partially compensate for low frequency attenuation of the first speaker without exceeding one or more acceptable limitations of the signal processing system. If boosting alone cannot completely compensate for low frequency attenuation of the first speaker without exceeding one or more acceptable limitations of the signal processing system, the level dependent bass management system processes the audio input signal using an alternate low frequency management solution.

Abstract: A computer audio system includes an audio codec and a lone controller. The audio codec is operably coupled to receive audio information, which includes tone control settings, PCM digital audio inputs and PCM digital audio outputs. In addition, the audio codec may receive audio information as analog input signals via a line-in, a CD input, or an auxiliary input. Based on the audio information, the audio codec provides a first stereo output, a second stereo output and a monotone audio output. The tone controller is operably coupled to the audio codec and includes a low pass filter, a high pass filter, a band pass filter, and a summing module. The low pass filter is operably coupled to filter the monotone audio output and isolates bass components of the audio signal being processed. By further coupling a volume control module to the low pass filter, the bass component of the audio signal being processed may be varied.

Abstract: An audio codec includes an input for receiving audio information. Audio processing circuitry produces a first stereo audio signal, a second stereo audio signal, and a monotone audio signal based on the audio information. A low pass filter filters the monotone audio output, wherein the low pass filter passes a bass component of the monotone audio signal substantially unattenuated and attenuates higher frequency components of the monotone audio signal. A high pass filter filters the first stereo audio output, wherein the high passes filter passes a treble component of the first stereo audio signal substantially unattenuated and attenuates lower frequency components of the first stereo audio signal. A band pass filter filters the second stereo audio output, wherein the band pass filter passes a mid band component of the second audio signal substantially unattenuated and attenuates low frequency components and high frequency components of the second stereo audio signal.

Abstract: The present invention provides for methods and systems for digitally processing audio signals by adjusting the gain of a signal a first time, using a digital processing device located between a radio head unit and a speaker. The methods and systems may filter the adjusted signal with a first low shelf filter, compress the filtered signal with a first compressor, process the signal with a graphic equalizer, compress the processed signal with a second compressor and adjust the gain of the compressed signal a second time. The methods and systems may also filter the signal received from the first low shelf filter with a first high shelf filter prior to compressing the filtered signal with the first compressor. The signal may be filtered with a second low shelf filter prior to processing the signal with the graphic equalizer. Some embodiments filter the signal with a second high shelf filter after the signal is filtered with the second low shelf filter.