Onkyo TX-SR304 5.1 Dolby Home Theater Receiver

Surround sound: Surround sound simulates the theater or concert experience by surrounding the listener with sound coming from different points around the room.

Bandwidth @ rated power: This is the frequency range the amp uses to achieve the claimed wattage.

Power per channel (RMS): This refers to the amount of power (watts) the source unit sends to the right and left front channels, as opposed to power sent to other speakers.

THD @ rated power: THD stands for total harmonic distortion and is rated as a percent of the total musical signal.

Composite video outputs: A basic video connection commonly found on VCRs, game consoles and camcorders. All video information is combined, and a comb filter must be used by the display device to break the signal down into the component parts. Not recommended for best picture.

HDMI inputs: The number of HDMI inputs a TV has. The more inputs, the more components can be added to the system.

Digital coaxial outputs: This connection carries up to 7 channels of digital audio for playback with a surround-sound receiver. Digital coaxial uses a standard RCA-type connector.

Digital audio (TOSLINK) outputs: This digital audio output allows for a connection to a home audio system. When using a TV’s built-in ATSC (HD) tuner, as with an antenna, the digital audio output is able to pass a Dolby Digital audio signal.

Stereo audio inputs: A set of RCA audio outputs that let you connect a TV to an audio system. This type of connection will only give you stereo, though many audio systems can turn into surround modes like Dolby Digital Pro Logic II for a more enveloping experience.

S-video inputs: This round connector carries video only, no audio, and while it will give you better picture quality than a Composite connection it is still limited to 480i resolution and cannot pass high-definition.

Number of component video inputs: These inputs use three RCA cables to carry a video signal. Receivers and sources with these inputs will be able to route video signals from more than one high-resolution source to a TV with component inputs.

Number of digital coaxial inputs: A single coaxial cable can transfer a multi-channel signal from a digital source, like a DVD player, to a receiver, where it will be processed and turned into surround sound. The more inputs you have, the more components you can hook up.