How Many Audio and Video Components Do You Want to Connect?
Audio and video inputs are important because they determine the number of components you can connect to your system. Consider the components you have now and those you might want to add in the future. At a minimum you will want to connect a DVD and/or CD player and a television, but you may want to add a DVR (Digital Video Recorder) or a cable or satellite dish receiver in the future. Digital (optical and coaxial) and analog audio connections are equally important.
Most receivers have six-channel analog inputs, which are very important for playback of the latest, high-resolution audio discs such as DVD-Audio or SACD. These discs offer significantly better fidelity than CDs but require a capable disc player and corresponding audio inputs on the receiver. The six-channel analog input may also be necessary for any future audio formats that come along. Lately, many higher priced receivers also offer an IEEE 1394 FireWire digital connection (also called i-Link) between the player and the receiver for digital connection of DVD-A and SACD players.
Video connections come in four types: composite, S-video, component video and the newest, HDMI (High Definition Multimedia Interface). Most new DVD players and television monitors have component video connections. Many receivers feature a circuit that up-convert all incoming video signals to component video with a single video cable connecting the a/v receiver with the TV, which simplifies connections and improves video quality. The bandwidth or frequency range of the component video circuit in the receiver is important for the highest video quality. Bandwidth, measured in megahertz (MHz), is a specification that indicates how much information can go from the source through the video circuits in the receiver to the television or monitor. More bandwidth generally means a better picture. The minimum bandwidth is about 30MHz, but 60-100MHz is better. Some higher priced receivers, such as the Yamaha RX-Z9 include video enhancement circuits to further improve picture quality. The latest HDMI connections offer the best performance and have the added advantage that one cable can carry audio and video signals, which helps reduce the snarl of wires connecting your components to the receiver.
Front panel A/V inputs on the receiver are important if you want to connect a video game console or a camcorder to the receiver without removing it from the cabinet or shelf to use the rear-panel connections. Typically front panel inputs are analog audio (sometimes digital audio, too) with composite or S-video inputs.

