An audio/video receiver (AVR) is a consumer electronics component used in a home theater. Its purpose is to receive audio and video signals from a number of sources, and to process them and provide power amplifiers to drive loudspeakers and route the video to displays such as a television, monitor or video projector.
An audio/video receiver (AVR) is a consumer electronics component used in a home theater. Its purpose is to receive audio and video signals from a number of sources, and to process them and provide power amplifier to drive loudspeakers and route the video to displays such as a television, monitor or video projector. Inputs may come from a satellite receiver, radio DVD players, Blue ray disk players, VCRs or video game consoles, among others. The AVR source selection and settings such as volume, are typically set by a remote controller
The term “receiver” basically refers to an amplifier typically at least a two-channel stereo model, that has a built-in radio tuner. With A/V receivers, the basic functionality is to receive an audio signal, amplify the audio signal to drive multiple speakers, and allow pass-through of the corresponding video signal to a display device such as a projector or a television. The receiver performs tasks that would otherwise require numerous separate pieces of equipment, such as preamplifiers, equalizers, multiple power amplifiers, and so on.
As home entertainment options expanded in the 1980s and 1990s, 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, though this role diminished again once TVs began supporting multiples of the same type of input connector.
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
How does an audio receiver work?
The receiver is at the heart of a typical home theater system. The receiver sends the video on to your television and sends the audio to the decoder. The decoder sorts out the different sound channels from the video signal, and then sends the information to amplifiers for each sound-channel output.
FEATURES OF DIGITAL AUDIO RECEIVER
The Ear Test
Sound quality is far and away the most important AV receiver criteria — but it’s also the most subjective. Some people want the sound of a receiver to be completely transparent, while others prefer receivers that lend the audio an extra touch of brightness or warmth. Many Yamaha AV receivers offer a feature called YPAOTM (Yamaha Parametric room Acoustic Optimizer), which analyzes the components you’ve got and the space you’re in, then calibrates the receiver’s audio output to those specs so that you always get the best possible listening experience in your particular listening environment.
Got the Power?
Every good AV system needs a powerful receiver, but figuring out the power rating of an audio component can be a challenge, with lots of numbers and strange terms getting in the way. The simple measurement of WPC (wattage per channel) is not necessarily going to help you very much, because it’s often determined in an old-fashioned way, by driving one channel with a simple test tone. This just isn’t realistic for a modern AV system, which uses at least two channels all the time (conceivably many more — see below) and is expected to cover an extremely wide frequency range with minimal amounts of THD (total harmonic distortion).
There’s a much better way to measure a receiver’s true power output, and that’s by seeing what happens when you drive two channels simultaneously with a wide range of tones — ideally everything between 20Hz and 20kHz (the range of human hearing). When measured by this standard, the Yamaha RX-V685, for instance, has an output power rating of 90 watts, with a THD of 0.06%. The 90 watts is far more than enough power for a standard-sized living room, and the extremely low THD value is a reflection of exceptionally clear sound quality.Yamaha RX-V685.
Let’s make the fairly safe bet that you’re interested in surround sound for your home system. The question is, how many channels will you need?
5.1 is the most common surround format. It consists of five discrete audio channels (the “5”) and one extra low-frequency (bass) channel designed to be routed to a subwoofer (the “.1”). 7.1 adds two more channels to the mix.
Once you move beyond 7.1 — to 9.1 or 11.1 — the additional channels are no longer discrete. Instead, they’re matrix-encoded, meaning that they are blended in with the real channels. It’s the job of your receiver’s processor to pick them out of the matrix and assign them to various speakers in the correct proportions, which makes your choice of receiver even more important.
Systems that are classified as “.2” rather than “.1” (5.2, 7.2, and so on) are designed to be used with two subwoofers instead of one, which gives a deeper sense of sub-bass and also enables the burden of the low end to be shared so that it doesn’t all depend on a single speaker. All Yamaha AV receivers allow for the use of at least one or two subwoofers.
The next step is multidimensional sound, in which there are height channels, which may come from in-ceiling or upward-firing speakers. Examples of multidimensional speaker configurations include 5.2.4, 7.2.2 or 7.2.4, where the last digit represents the number of height channels. Because there is essentially no limit to the amount of channels, this type of audio has to be matrix-encoded since dozens of discrete channels would require you to have dozens of speakers — an impracticality for most people. Dolby’s version is called Dolby Atmos®, while the format offered by DTS is called DTS:X™. All Yamaha AVENTAGE receivers and some Yamaha RX-V and TSR models have both Dolby Atmos and DTS:X capability.
Ins and Outs
Of course, a receiver has to be able to accommodate every other part of your system. Be sure to check the exact number and type of inputs and outputs needed for each of your separate components, and match them up with what the receiver is offering. Err on the side of too much rather than too little; after all, you may well want to add more components later.
As an example, the Yamaha RX-A3080 AV receiver provides a wealth of interconnections. In the back, there are seven HDMI inputs, three HDMI outputs, one network port, three optical digital audio inputs, three coaxial digital audio inputs, ten analog stereo inputs, four composite video inputs and connections for an AM/FM antenna, plus outputs for up to eleven speakers and two subwoofers. In front, there’s a 1/4″ stereo headphone jack, a USB port, a 1/8″ analog mini-jack, and an input for the supplied YPAO microphone used to automatically calibrate the output of your speakers based upon the acoustic characteristics of your room.Yamaha RX-A3080 front.Yamaha RX-A3080 rear.
Not that long ago, you couldn’t put an AV system together without a bucketful of wires. That time has passed, and now a major test of a receiver is its ability to work with a variety of wireless devices. Some receivers, like Yamaha AV models equipped with MusicCast Surround, even allow you to use wireless surround speakers like the MusicCast 20 and MusicCast 50 to easily create a home theater with surround sound without having to run wires around your room. Connectivity via Wi-Fi®, Bluetooth® or AirPlay® 2 enables access to streaming services, as well as the music stored on your smart devices and computers; it also allows remote control from a smartphone or tablet.
MusicCast technology also allows you to add wireless speakers, sound bars or other devices in up to 31 other rooms at full fidelity, giving you the ability to listen to your favorite music throughout your entire home, all under the control of a simple app — and without the need for cabling.
ADVANTAGES OF DIGITAL AUDIO RECEIVER
Users of wireless microphone and in-ear monitor systems have faced several disruptive challenges in recent years. From the Digital Dividend to the continuing development of 4G/ LTE networks, all have led to uncertainties. Most recently, OfCom added fuel to the fire by announcing their intentions to clear the 700MHz band as early as 2020. Needless to say, these changes continue to have huge implications for wireless microphone users, and subsequently, you need to select your system carefully.
One way to address some of the challenges of an increasingly uncertain future for RF is to select a digital wireless system. In addition to their transparent sound quality, digital wireless systems offer a number of advantages as follows:
Crystal Clear Audio at All Times
Digital systems can transmit a flat frequency response across the entire audible range, meaning the sound of the capsule is not affected by the wireless components in the same way an analogue system might be. Digital wireless systems convert analogue audio to a digital signal that modulates a radio carrier in discrete steps (ones and zeroes). The result is a digital audio signal that arrives at the receiver unaffected by the radio link. Also, any RF noise that may be present below a certain threshold doesn’t affect the audio quality. Instead, the audio is always crystal clear without any added noise.
Batteries Last Longer
Digital wireless microphone systems have 30–40% longer battery life than equivalent analogue systems. For example, the Shure digital ULX-D transmitters run up to 11 hours on two AA alkaline batteries and more than 12 hours with the Shure SB900 Lithium-ion Rechargeable Battery.
Superior Spectral Efficiency
As briefly touched on at the beginning of this article, the amount of clear spectrum available to users of wireless systems has been significantly reduced in recent years. While greater efficiency isn’t necessarily true of all digital wireless systems, the modulation type chosen by the manufacturer can potentially lead to much higher channel counts as explained below:
Higher channel counts are possible because the deviation of a digital wireless signal is more predictable than that of a frequency modulated analogue signal, allowing tighter channel-to-channel frequency spacing. Depending on the manufacturer and model, digital systems can often deliver nearly twice the channels in the same slice of spectrum as their analogue counterparts. This feature can be worth its weight in gold when facing an increasingly crowded RF environment.
Some systems such as Shure’s ULX-D, take spectral efficiency to a completely new level by using High Density Mode. This unique mode further reduces the required space between active transmitters and permits for 63 wireless microphones to work in only 8MHz! This type of usage is incredibly valuable in installations or events that require a huge number of wireless channels across a larger venue where they are not used in a single space.
What Are the Disadvantages of Digital Wireless Systems?
Latency is commonly regarded as the main disadvantage of digital wireless. Latency is the amount of time it takes for a signal to arrive at the output after entering the input of a digital device. While large latency values could potentially be problematic, most high-quality digital systems produce less than 5 milliseconds of latency, which is acceptable to most listeners. On the contrary, latency is not a factor in analogue equipment as there is no conversion from analogue to digital and back.
Become a Wireless Expert
Changes to RF spectrum have come thick and fast in recent years. Wireless microphone and in-ear users have been significantly affected by changes as a direct result of the switchover to digital TV and the subsequent expansion of mobile broadband services. Keep up to date with the latest changes and get your free guide to wireless frequencies in the UK by visiting LosingYourVoice.co.uk