Abstract: Techniques for controlling one or more audio amplifiers in or associated with a device coupled on a local area network are disclosed. An example playback device includes a processor, an amplifier, a network interface, and a memory. The memory includes a software module that, when executed by the processor, causes the playback device to: operate in a first power mode in which the amplifier consumes a first amount of power while operating in the first power mode, determine that a defined time has passed since receiving, via the network interface, a specified type of data packet; and based on determining that the defined time has passed since receiving the specified type of data packet, transition from operating in the first power mode to operate in a second power mode in which the amplifier consumes a second amount of power, wherein the first amount of power is greater than the second amount of power.

Abstract: Techniques for controlling one or more audio amplifiers in or associated with a device coupled on a local area network are disclosed. The device receives at least one selected source from other devices also coupled on the network According to one aspect of the techniques, an automatic shutdown control module is provided in the device to power down the audio amplifiers when there is no audio data flow coming to the device or power up the audio amplifiers when there is audio data flow coming to the device. In one embodiment, the procedure to power down or power up the amplifiers is in accordance with a hysteresis, wherein the hysteresis, being lagging of an effect behind its cause, protects the amplifiers and makes the powering-down or powering-up procedure unnoticeable to a user.

Abstract: Techniques for controlling one or more audio amplifiers in or associated with a device coupled on a local area network are disclosed. The device receives at least one selected source from other devices also coupled on the network According to one aspect of the techniques, an automatic shutdown control module is provided in the device to power down the audio amplifiers when there is no audio data flow coming to the device or power up the audio amplifiers when there is audio data flow coming to the device. In one embodiment, the procedure to power down or power up the amplifiers is in accordance with a hysteresis, wherein the hysteresis, being lagging of an effect behind its cause, protects the amplifiers and makes the powering-down or powering-up procedure unnoticeable to a user.

Abstract: Techniques for controlling one or more audio amplifiers in or associated with a device coupled on a local area network are disclosed. The device receives at least one selected source from other devices also coupled on the network According to one aspect of the techniques, an automatic shutdown control module is provided in the device to power down the audio amplifiers when there is no audio data flow coming to the device or power up the audio amplifiers when there is audio data flow coming to the device. In one embodiment, the procedure to power down or power up the amplifiers is in accordance with a hysteresis, wherein the hysteresis, being lagging of an effect behind its cause, protects the amplifiers and makes the powering-down or powering-up procedure unnoticeable to a user.

Abstract: Techniques for processing input signals in accordance with an output configuration are disclosed. According to one aspect of the techniques, a module implemented in a sound reproducing device is configured to determine whether a sound in the input audio source can be reproduced properly through speakers of an output configuration of the device by examining the sound effects in the input audio sound and the output channel in the output configuration, producing synthetically a sound effect if the number of sound channels is greater than the number of sound effects, or reducing synthetically a sound effect if the number of sound channels is less than the number of sound effects.