Example embodiments provide a process that includes one or more of receiving an audio signal from a feedback path of a feedback compressor circuit, determining whether an auxiliary attenuation value applied to the feedback compressor circuit has changed since a last audio signal was received, responsive to determining the auxiliary value has changed, determining a current operational state value of the LPF needs to be modified based on the changed auxiliary attenuation value, modifying the operational state value of the LPF, and applying the audio signal to the modified LPF.

Example embodiments provide a process that includes one or more of receiving an audio signal at a feedback compressor circuit, receiving an auxiliary attenuation signal from an auxiliary attenuation source, determining a threshold power level based on a value of the auxiliary attenuation signal, determining an output power level of the audio signal exceeds the threshold power level, combining the audio signal with the auxiliary attenuation signal from the auxiliary attenuation source and a compressed attenuation signal from the feedback compressor circuit to create a combination signal, and generating an audio output signal of the feedback compressor circuit based on the combination signal.

The invention relates to a method for protecting a component (6) within an audio device (4) from the exceedance of a maximum internal temperature (TI), wherein a power loss (V) of the component (6) is determined, a measurement temperature (TM) is measured on the component (6), a temperature difference (DT) for the component (6) between the measurement temperature (TM) on the component and the internal temperature (TI) is determined from the power loss (V) by means of a thermal model (14) of the component (6), the internal temperature (TI) is determined as the sum of the measurement temperature (TM) and the temperature difference (DT), a permissible maximum value (VM) for the power loss (V) is determined on the basis of the internal temperature (TM) and known component data (16) of the component (6), and the component (6) is operated in a normal operating mode (N) if the power loss (V) does not exceed the maximum value (VM) or the component (6) is otherwise operated in reduced-power economy operating mode (S) such that the power loss (V) is limited to the maximum value (VM). An audio apparatus (2), having an audio device (4) that internally contains a component (6) that should be protected from the exceedance of a maximum internal temperature (TI), contains a protection module (8) for carrying out the method according to the invention.

Example embodiments provide a process that includes one or more of receiving an audio signal at a feedback compressor circuit, receiving an auxiliary attenuation signal from an auxiliary attenuation source, determining a threshold power level based on a value of the auxiliary attenuation signal, determining an output power level of the audio signal exceeds the threshold power level, combining the audio signal with the auxiliary attenuation signal from the auxiliary attenuation source and a compressed attenuation signal from the feedback compressor circuit to create a combination signal, and generating an audio output signal of the feedback compressor circuit based on the combination signal.

A circuit includes a tracking control module that receives an input voltage and a dynamic reference voltage. The tracking control module generates a swing-limited output voltage to mitigate over-voltage swings of the input voltage. The tracking control module includes a bias tracker that receives the dynamic reference voltage and generates a reference tracking control signal that tracks voltage changes in the dynamic reference voltage. A swing-limiter receives the reference tracking control signal and the input voltage. The swing-limiter limits the magnitude of the received input voltage based on a threshold and adjusts the swing-limited output voltage in response to the reference tracking control signal.

In some embodiments, a method for performing enhancement on an audio signal to generate an enhanced audio signal in response to feedback indicative of amount of compression applied to at least one frequency band of the enhanced audio signal. In typical embodiments, the enhancement is or includes bass enhancement. Examples of other types of enhancement performed in other embodiments include dialog enhancement, upmixing, frequency shifting, harmonic injection or transposition, subharmonic injection, virtualization, and equalization Other aspects are systems (e.g., programmed processors) and devices (e.g., devices having physically-limited bass reproduction capabilities, such as, for example, a notebook, tablet, mobile phone, or other device with small speakers) configured to perform any embodiment of the method.

An active limiting system that is suitable to protect a low noise amplifier against the high power signals received from a signal input includes, at least one first switch, source of which is connected to a gate voltage; at least first resistor which is connected between the gate and source of the first switch; at least one second resistor, which is connected between a drain voltage and drain of the first switch; at least one second switch, source of which is connected to said drain voltage and drain of which is connected to a signal input; at least one third resistor which is connected between the drain of the first switch and gate of the second switch; at least one first filtering element, which blocks DC currents/voltages and which is connected between the source of the second switch and ground.

An audio system, including at least one approximating circuit, the at least one approximating circuit configured to apply an approximated gain to the input signal, the least one approximating circuit outputting an approximated signal; a limiter configured to reduce a magnitude of the input signal by a gain determined by an amount the magnitude of the approximated filtered signal exceeds a predetermined threshold, the limiter outputting a limited input signal; a filter being respectively configured to receive the limited input signal and to respectively apply a filter gain, the filters outputting a plurality of filtered signals, wherein the approximated gain is substantially similar to the filter gain of one of the plurality of equalization filters; and a speaker array comprising a plurality of speakers, each speaker configured to receive a respective filtered signal of the plurality of filtered signals and to transduce the filtered signal to an audio signal.

Example embodiments provide a process that includes one or more of receiving an audio signal at a feedback compressor circuit, determining how much to attenuate the audio signal when a power level of the audio signal exceeds a threshold power level, combining the audio signal with an auxiliary attenuation signal from an auxiliary attenuation source and a compressed attenuation signal from the feedback compressor circuit to create a combination signal, and generating an audio output signal of the feedback compressor circuit based on the combination signal.

A limiting amplifier circuitry according to the disclosure includes: a first differential amplifier circuitry capable of adjusting, as voltage offset, a difference between direct-current voltage components of first differential signals input thereto, the first differential amplifier circuitry amplifying the first differential signals and outputting the amplified first differential signals as second differential signals; a second differential amplifier circuitry that amplifies the second differential signals with an amplification factor depending on a difference between direct-current voltage components of the second differential signals; a signal detecting circuitry that detects an amplitude of the second differential signals, determines whether or not the amplitude is larger than a threshold, and outputs a determination result; and an offset control circuitry that controls the voltage offset by using the determination result.