What is an AV Receiver?
The AV receiver is the device where everything comes together in a home theater. It receives picture and sound from consoles, players, or streaming boxes, forwards the picture to the TV, and distributes the sound to the connected speakers. AV simply stands for Audio and Video.
Many people today use a soundbar or a TV voice amplifier instead of an AV receiver. However, if you want to operate multiple speakers in a room for a classic home theater, you usually still need a central solution for picture and sound. The name can be particularly confusing because three different things in the living room are called “receiver” or “AV.”
The Functions of an AV Receiver
An AV receiver performs several tasks simultaneously. Previously, individual devices were needed for this, but today everything is contained in one housing. Accordingly, these devices can be large and heavy.
Control Center for Picture and Sound
On the back of the device are several HDMI inputs, where game consoles, Blu-ray players, and streaming boxes can remain connected simultaneously without having to touch any cables when switching between them. The receiver passes the picture from the currently selected source to the TV and keeps the sound. Switching is done on the receiver, not the TV.
Practically, this means the TV stays permanently on a single input. The receiver’s remote control handles everything else. Many devices even turn on together via device control.
A TV often has only two or three HDMI ports. If you operate consoles, players, and streaming boxes simultaneously, you would constantly have to swap cables without an AV receiver.
Amplifier for Passive Speakers
Passive speakers do not have their own amplifier or power outlet; instead, they need a device to supply them with power, and the receiver performs exactly this task for each connected channel individually. This is identifiable by the screw terminals on the back, where bare speaker cables are clamped.
The power output per channel is listed in watts on the data sheet. However, these specifications are hardly comparable between manufacturers because they are measured differently. In a normal living room, devices operate far below their limit anyway.
Decoder for Multi-Channel Audio
Audio from movies and television usually arrives compressed, for example, as Dolby Digital or DTS. Someone needs to unpack this data stream and distribute it to the individual speakers. In a home theater, this is the receiver. For more complex formats like Dolby Atmos, it also calculates height information. If only stereo is available, many devices can artificially create multiple channels from it. Whether one likes this or not is a matter of taste. However, it can also simply be switched off.
Three Devices All Called Receivers
In the living room, “receiver” can mean very different things. It can refer to the AV receiver, the reception box for satellite or cable, or sometimes just the old colored jacks on the TV.
The Receiver for TV Reception
The term “receiver” also appears in TV reception. However, this does not refer to an AV receiver, but rather a box that receives the TV signal and passes it on to the television. Such devices exist, for example, for satellite or cable reception.
This reception box only shares the name with an AV receiver. It handles TV programming, while the AV receiver processes picture and sound signals from various devices and powers the connected speakers.
Many modern televisions already have built-in receivers for satellite and cable. Therefore, an additional box is often only needed if the provider requires it for specific programs, functions, or reception methods.
The AV Connection on the TV
On older TVs, AV refers to the three colored RCA jacks: yellow for video, red and white for audio. These were previously used to connect VCRs and game consoles. They are usually missing on new devices because HDMI transmits both over a single cable.
This has nothing to do with the AV receiver, apart from the two letters in the name.
Channels, Connections, and Calibration
Numbers like 5.1 or 7.2 are often found on the packaging. These are power specifications and indications for automatic calibration. Among other things, they show how many speakers and source devices can be connected and what setup options the receiver offers. Additionally, there are indications of supported audio formats like Dolby Atmos or DTS:X.
The Number Combinations on the Packaging
The first number represents the possible speakers in the room. The second, in an audio format like 5.1, stands for the additional channel with deep effects. For a device specification, however, it usually indicates the number of subwoofer outputs. Behind 7.2, there are correspondingly seven speakers and two connections for subwoofers. If a third number appears, it indicates height speakers for the ceiling or up-firing speakers that reflect sound from above.
| Specification | What it means |
|---|---|
| 2.0 | two speakers, i.e., classic stereo without a subwoofer |
| 2.1 | two speakers and one connection for a subwoofer |
| 5.1 | three speakers in front, two in back, plus the channel for deep effects |
| 7.2 | seven speakers distributed in the room, plus two subwoofer connections |
| 5.1.2 | like 5.1, plus two height speakers |
More channels mean more speakers in the room and more cables to lay.
HDMI Inputs and the Return Path to the TV
The number of HDMI inputs determines how many source devices can remain permanently connected. For the return path, there is a special port, marked with ARC or eARC. This allows the TV to send the audio from its own apps and TV programs to the receiver without needing a second cable.
If this connection is not available, TV audio can also be sent to the receiver via the optical output. However, the audio formats there are limited, and the volume is then usually controlled on the receiver.
Automatic Calibration
Many AV receivers come with a small calibration microphone that you place at the listening position. The receiver plays test tones and then adjusts the levels and delays of the individual speakers. This way, levels and delays are adapted to the different distances and conditions in the room.
However, calibration cannot compensate for all audio problems in the room. Strong reverberation, for example, will persist. Afterward, each channel can be individually fine-tuned, which can be particularly useful for the center speaker.
AV Receivers and Speech Intelligibility
Many people buy a system because their TV sound sounds thin. For impact and spatial effect, this indeed makes a big difference. However, if you primarily want to understand dialogues better, an AV receiver does not automatically provide more. In this case, it is often more sensible to consider a TV voice amplifier.
The Center Speaker
In a large surround system, the center speaker primarily handles voices and dialogues. It is usually placed directly below or above the TV and can be adjusted louder or softer separately on the AV receiver. So, if you want to emphasize speech a bit more, this provides a direct point of adjustment.
For multi-channel audio, there is a dedicated center channel. This channel is absent in stereo. While the receiver can distribute the signal to multiple speakers depending on the mode, this is not true separate dialogue control and optimization.
Space, Cables, and Operation
For a classic home theater with multiple speakers, the AV receiver is a central component. This involves laying cables throughout the room, finding optimal placements for the speakers, and an additional device that needs to run and be operated every TV evening. However, those who primarily watch regular television and do not want to set up a surround system often do not need this effort.
The distance between speakers and the listening position still remains. Therefore, those who have difficulty understanding speech do not automatically benefit from more speakers. If speech intelligibility is the main priority, a solution closer to the seating position can address this problem more effectively.
Frequently Asked Questions
That depends on who you ask. In reception technology, “receiver” refers to the box that decodes the satellite or cable signal and delivers the program to the TV. In audio technology, “receiver” refers to the AV receiver, which is the amplifier with a switch for multiple sources. If you want to know which device you have, turn it around. Only the AV receiver has screw terminals for speaker cables.
Mainly if passive speakers are to be used in the room, if a surround or Atmos setup is planned, or if multiple source devices are to remain permanently connected. For normal TV viewing with two devices connected via HDMI, it is overkill. Active speakers, a soundbar, or a solution near the seating position can do without it. So the question is less about sound quality and more about the planned setup in the room.
Even a stereo amplifier can have multiple inputs and additional functions. An AV receiver additionally processes video signals and multi-channel audio, selects the source, and powers five, seven, or more speakers. A stereo amplifier remains at two channels and does not pass video to the TV. In older systems, these tasks were distributed among several devices.
It is useful if multiple passive speakers are to be placed in the room, if a surround or Atmos setup is planned, or if multiple source devices are to remain permanently connected. For a simple TV setup with one or two devices connected via HDMI, it is not necessary. Soundbars now cover this area and do not require cable laying. The decision therefore depends on the planned setup and not solely on sound quality.
If the TV lacks an HDMI port with ARC, the optical output remains as a path to the receiver. This allows stereo and common compressed multi-channel formats to pass through, but the path is too narrow for high-bitrate versions. Very old devices only offer the red and white RCA jacks, which exclusively provide stereo. In both cases, an additional HDMI cable from the receiver to the TV is needed if video from a source device is to be displayed.