When you want to make big noise in your theatre, an AV receiver is the key.

An audio-video (AV), or surround sound, receiver is the hard working hub of any home theatre. It contains the decoding chips that unlock the multichannel soundtracks encoded on discs, videotapes and TV broadcasts, but also the five or more amplifiers that drive the speakers in your theatre room. It?s also the machine that all your other equipment connects to, allowing you to switch between CD, VCR and DVD, for example, and adjust volume using just a single remote.

Home theatre-in-a-box systems squeeze all this functionality into the same chassis as a DVD player, and while this DVD-receiver approach is neat it has performance limitations. The most obvious is volume. While ?big? sound has much to do with speaker design, well-powered amplifiers are the key to achieving high volume levels.  The amplifiers in home theatre in a box systems are necessarily made small and, typically, don?t produce sound ?big? enough to match the images on a large screen, especially a plasma or projection system. So if you want big sound, how much power do you need from an AV receiver?