A signal processing apparatus includes a first signal processing circuit configured to generate a first sound signal based on an input signal, and a second signal processing circuit configured to generate a second sound signal based on the first sound signal. In a case that a gain of the first signal processing circuit is switched, the second signal processing circuit generates, for a predetermined time after the gain of the first signal processing circuit is switched, a value of the second sound signal based on a value of the first sound signal at or before a timing of the gain of the first signal processing circuit being switched.

Disclosed herein are signal amplifier architectures that provide a plurality of gain modes. Different gain modes can use different paths through the amplifier architecture. Switches that are used to select the path through the amplifier architecture can be configured to also provide targeted impedance in a degeneration block or matrix. The switches that select the gain path are provided in the amplifier architecture and are thus not needed or used in the degeneration block, thereby reducing the size of the package for the amplifier architecture, improving the noise figure (NF), improving impedance matching, and eliminating the need for control logic associated with the degeneration block or matrix.

In one example, a zone player may include a network interface, at least one processor, a non-transitory computer-readable medium, and program instructions stored on the non-transitory computer-readable medium that may be executable by the at least one processor such that the zone player is configured to receive an instruction to change a volume setting of the zone player to a requested volume level; in response to receiving the instruction to change the volume setting of the zone player to the requested volume level, adjust the volume setting of the zone player to an adapted volume level that is lower than the requested volume level; and after adjusting the volume setting of the zone player to the adapted volume level, send an indication that the volume setting of the zone player has been adjusted to the requested volume level rather than the adapted volume level.

An apparatus includes a controller that controls operation of an amplifier. The amplifier receives a sample voltage produced by a resistive path; the sample voltage from the resistive path is indicative of a magnitude of current through a motor winding. The controller selects a gain setting to apply to the amplifier based on one or more conditions. The selected gain setting is selected amongst multiple possible gain settings. Subsequent to selection, via application of the selected gain setting to the amplifier, and based on an output of the amplifier, the controller monitors a magnitude of the current through the motor winding. According to one configuration, the amplifier adjusts the magnitude of the selected gain setting depending on one or more parameters such as the magnitude of the current through the motor winding, a selected operational range of controlling current through the motor winding, etc.

An example playback device includes a first interface for receiving a first audio signal from a first audio source; a second interface for receiving a second audio signal from a second audio source; and a processor configured to: cause the playback device to playback the second audio signal; determine that the first audio signal is present at the first interface; in response to determining that the first audio signal is present at the first interface, (i) cease playback of the second audio signal being played by the playback device and (ii) cause the playback device to playback the first audio signal; receive an instruction to stop the playback device from playing the first audio signal while the first audio signal is still present at the first interface; and arm the playback device such that a subsequent presence of the first audio signal at the first interface causes the playback device to play the first audio signal.

Various implementations include systems for amplifying input signals. In particular implementations, a system includes a common mode voltage controller configured to receive an input signal and output a pair of adjusted signals; a modulator that generates a pair of pulse width modulation (PWM) signals in response to the adjusted signals; and a self-boosting push pull amplifier configured to receive the PWM signals and generate an amplified output, wherein the self-boosting push pull amplifier is configured to generate a differential mode voltage representative of an amplified version of the input signal, wherein the adjusted audio signals generated by the common mode voltage controller include a dynamically adjusted gain and duty cycle offset that causes the self-boosting push pull amplifier to operate with a reduced common mode voltage.

The detection matrix for an Orthogonal Differential Vector Signaling code is typically embodied as a transistor circuit with multiple active signal inputs. An alternative detection matrix approach uses passive resistor networks to sum at least some of the input terms before active detection.

In an embodiment, a class-D amplifier includes an input terminal configured to receive an input signal; a comparator having an input coupled to the input terminal; a deglitching circuit having an input coupled to an output of the comparator; and a driving circuit having an input coupled to an output of the deglitching circuit. The deglitching circuit includes a logic circuit coupled between the input of the deglitching circuit and the output of the deglitching circuit. The logic circuit is configured to receive a clock signal having the same frequency as the switching frequency of the class-D amplifier.

There is disclosed a method and system for selecting an audio preset for an audio processing engine. A selection of an audio track may be received. Audio corresponding to the audio track may be output. A selection to display audio presets may be received. A carousel user interface may be displayed, where the carousel user interface comprises images corresponding to audio presets. A selection of an audio preset may be received via the carousel user interface. The audio preset may be applied to the audio processing engine. The audio processing engine may generate an audio stream based on the audio track. The audio stream may be output.

An example first playback device includes programming to perform functions including: (1) storing an active volume state variable in memory, wherein the active volume state variable corresponds to a current playback volume; (2) storing a volume limit state variable in memory, wherein the volume limit state variable corresponds to a playback volume limit of the first playback device; (3) detecting a command to begin playback of media at a proposed playback volume different from the current playback volume; (4) based on comparing (i) the playback volume limit and (ii) the proposed playback volume, selecting a startup playback volume; (5) playing back media at the startup playback volume; and (6) causing at least a second playback device of the media playback system to play back media at the startup playback volume.