AV receiver

An audio/video receiver (AVR) is a consumer electronics component used in a home theater. Its primary purpose is to receive audio and video signals from a number of sources, processing them to drive loudspeakers and a display. Possible displays include television, monitor, or video projector while the inputs may come from television, satellite receiver, radio, DVD players, Blu-ray Disc players, VCRs, and video game consoles.

The AVR source selection, and settings such as volume, are typically set by a remote controller.

The term receiver basically refers to an amplifier that has a built-in radio tuner. With A/V receivers the basic functionality is to receive an audio signal, amplify the audio signal, and allow pass-through of the corresponding video signal to a display device such as a projector or a television.

As home entertainment options expanded, so did the role of the receiver. The ability to handle a variety of digital audio signals was added. More amplifiers were added for surround-sound playback. Video switching was added to simplify changing from one device to another. Within the last few years, video processing has been added to many receivers.

The term audio/video receiver (AVR) or Home Theater Receiver is used to distinguish the multi-channel audio/video receiver (home theater receiver) from the simpler stereo receiver, though the primary function of both is amplification.

AV receivers may also be known as digital audio-video receivers or digital media renderers.

The AV receiver is classified as an audio frequency electronic amplifier. But with the rapid addition of several features, AV receivers now generally have significant additional functionality.

Stereo receivers have two channels of amplification, while AV receivers may have more than two. The standard for AV receivers is five channels of amplification. These are usually referred to as 5.1 receivers. This provides for a left, right, center, left surround and right surround speaker to be powered by the receiver. 7.1 receivers are becoming more common and provide for two additional surround channels, left rear surround and right rear surround. The ".1" refers to the LFE (low-frequency effects/bass) channel, the signal of which is usually sent to an amplified subwoofer unit. 5.1 and 7.1 receivers don't usually provide amplification for this channel. Instead, they provide a line level output.

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