Welcome to the weird world of receivers! If you have just started exploring receiver options for your stereo or home theatre system, you probably already know that there is a steep learning curve involved if you want to know everything about them. It gets worse when you are bombarded with a bunch of indecipherable acronyms that manufacturers seem to think are as common as "TV." Do you really need all of that information about receivers in order to buy one that will serve your purposes?  Unless you're a real audiophile, you don't need to know everything, but there is some essential information about receivers that will save you from being disappointed by the one you purchase.

Types of Receivers

Audio Receivers

Audio receivers are designed purely for listening to music in stereo. They usually come with 2 channel output plus a third output for a subwoofer. This will be listed in shorthand as 2.1. Occasionally you will see 2.2 Channel receivers. These have connections for two stereo speakers and two subwoofers.

AV Receivers

Many households today are opting for AV (Audio Visual) receivers for all of their home entertainment needs. AV receivers are able to process signals from both audio and visual sources. They come with anywhere from 5.1 to 7.2 channels for surround sound effects. You can play CDs and get full stereo sound from the main speakers and the subwoofer(s) or play DVDs and get sound from all of the speakers.

Audio versus AV Receivers

Since you have more options with AV receivers, at first glance it may make more sense to forget about audio receivers. However, if you're on a budget, want great sound quality for your stereo and aren't yet ready for a full home theatre package, don't rule out audio receivers. You can get better stereo sound quality for less money this way. If you later want to hook up your sound system to your TV, look for front AV connectors, for ease of use.

Decoding the Specifications

Dolby and DTS

There are two major brands of sound technologies - Dolby and DTS. Dolby was the first to come out with surround sound systems and is the best known of these two major systems. DTS stands for "Digital Theatre Systems" and many experts argue that it is superior to Dolby. Each brand offers many sub-systems as well, which are basically improvements on their original technologies. Virtually all receivers will ome with Dolby Digital and a DTS decoder. For more advanced capabilities like Full HD and for 7.1 speaker systems, look for Dolby's TrueHD and DTS-HD. Better receivers will have a long list of Dolby and DTS features, but these are the important ones to look for.

HDMI

Newer AV receivers are coming standard with HDMI input and/or output. This stands for High Definition Multimedia Interface. This is an important feature to look for. HDMI inputs can accept input from gaming systems, Blu ray players, satellite receivers and cable TV boxes. Through the HDMI output jack, it then sends the appropriate video signals to the TV. You want to have at least one HDMI input jack, but 2 or more would be even better, to cover future needs.

About Power

The power specifications for receivers are very important, but unfortunately, manufacturers sometimes use sleight of hand to try to make their power specs look more impressive. These are the two most important numbers to look for:

100W per channel

In a 7.1 speaker system, the built-in amplifier in the receiver will be sending power to 8 speaker channels. If you want to get quality sound from your speakers, try to get 100W per channel and even more for your subwoofer. 

20-20,000Hz

This is where the manufacturers fudge with the numbers. Most consumers know about watts, but not about Hertz (Hz). Hertz is how sound frequencies are measured. In some receivers, their amplifiers do have 100W output, but only to a single frequency - 100Hz, for example. What this means is that when all channels are in operation, there will be a significant dropping of power at the high and low ends of the frequency band, resulting in poor quality sound. Look for 100W, 10-20,000Hz if you want quality sound.

Other Bits and Pieces

Some receivers have extra features that make them perform even better. Room Calibration, for instance, is a very cool feature some AV receivers come with that automatically calculates room acoustics and makes adjustments in the speakers to maximize their efficiency.

Another cool option for surround-sound systems is auto set up and calibration. Different manufacturers use different names for this, but basically it helps you locate the ideal positioning of your speakers in the room. Sony's system is called Digital Cinema Auto Calibration (DCAC). Others are the Audyssey and MCACC systems.

And finally. . .

AV receivers have been changing rapidly in order adapt to new video technology and still must compete with each other on price. You can get very good receivers surprisingly cheap when they are superseded by newer models.

We suggest that whatever you buy, look for HDMI digital inputs and outputs, at least one USB input and a number of digital coaxial input jacks. This way, you can use your receiver with the widest available range of devices. If you are looking for AV Receivers, think ahead and get a model that is HD and even 3D ready. It's just a matter of time before these replace SD (Standard Definition) TV altogether.