AV recieiver – audio must-haves
While an AV receiver is an extremely useful tool for video, where it really earns its keep is in the audio department. Indeed, receivers are primarily audio devices, and you can consider video functionality a very useful bonus.
An AV receiver performs as the amplifier for all your music and movie needs, sending audio out to up to eight connected speakers and a subwoofer. If the built-in amplifiers don’t drive your speakers loud enough for your tastes, many AV receivers also provide a set of pre-outs for connecting more powerful amplifiers.
The AV receiver is also what takes the stream of encoded data off a DVD or Blu-ray disc’s Dolby or DTS audio track and decodes it for playback through your speakers. Being the centre of surround sound operations in a home entertainment system, an AV receiver must include both Dolby Digital and DTS surround support, as these formats are present on DVDs and all Blu-ray discs. Ideally, a receiver you buy today should also support the new high resolution versions of these formats, these being Dolby TrueHD and DTS-HD Master Audio. Available only on Blu-ray disc, these make for the ultimate HD audio experience.
An AV receiver is a complicated piece of kit, and as with all things audio, extremely subtle when it comes to setup. You could spend days trying to get the balance of five, six or eight speakers just right, so good receivers include an auto-calibration function.
This takes the form of a special stereo microphone you plug into the receiver. You then place the microphone in the usual sitting position, and hit Go. The receiver will play a series of tones through the speakers (including some very odd thumping noises from the subwoofer!) and the microphone will measure the balance of how each sound reached it.
Afterwards, the receiver will tweak its output to each speaker by a decibel or two, either up or down. As a result, the particular architectural oddities of your room are overcome, and you’ll enjoy a perfectly balanced surround experience.
Speaking of output, AV receivers have a power rating, in watts. More watts typically equals a higher total volume (although your speakers will affect this), but power output is also about quality, not just noise. Generally, if your receiver offers 100 watts or higher per channel, it’s got the grunt necessary for a cinema-like audio experience. The neighbours will complain!
Then again, if you’re into discreet late-night listening, you can make use of the receiver’s headphone socket. Yes, it bypasses the surround sound capabilities of the device and outputs a stereo signal, but it’s still a very high-quality signal, and you’ll still have all the benefits of switching between sources, video upsampling and the other conveniences of an AV receiver.
Depending on the model, these can include iPod connectivity, with the ability to control the playlist and view artwork from your TV using the AV receiver’s remote; a second zone function for listening to music from, say a CD, via a pair of speakers in one room while surround plays in another; a USB port for connecting a hard drive chock full of songs and photos to be enjoyed via your entertainment system; CEC control for controlling other devices connected over HDMI using just the AV receiver’s remote; circuitry for improving the quality of compressed music, and a network connection for receiving internet radio stations or accessing tunes stored on a remote PC.
The power, surround support, convenience features and number and type of connections you’ll need from an AV receiver should not be determined by the system you currently have, but on the one you want. Shoot for the maximum your budget will allow in each of the above categories and you’ll land an AV receiver best able to feed your growing home theatre habit into the future.
Whether you’re a first-timer or upgrading your existing AV receiver, look for these features:
- 3x HDMI inputs – at a minimum!
- Decoding for major surround sound formats, including new Dolby TrueHD and DTS HD Master Audio Blu-ray
- Auto room calibration
- Video upscaling to 1080p
- A headphone socket