This glossary gives you the most basic definitions of all the words associated with home cinema.

Home cinema/ Home theater:
An entertainment system for the home that usually consists of a large television with video components (as a DVD player and VCR) and an audio system offering surround sound

Subwoofer
A speaker that is designed to reproduce the lowest of audible frequencies (usually below 80 Hz)

Surround Sound
Describes several types of processes that enable listener to experience sound coming from all directions

Bit rate
Number of bits that pass given point in telecommunication network in given amount of time (usually one second) – usually measured in multiple bits, i.e. kilobits (Kbps)

Bit stream
Describes binary bits of information transferred from one device to another; in home theaters it rather refers to audio signals from a source component to a preamplifier for decoding and distribution for the final sound reproduction

Decoder
Device that undoes the encoding so that original information can be retrieved and is interpretable again (opposite of an encoder)

DVD
Digital Versatile Disc (sometimes also referred to as Digital Video Disc -> technically not correct); DVD’s are used to store video, audio, image, or other computer data; Storage capacity goes from 4.5GB to about 17GB

HDMI (High Definition Multimedia Interface)
High Definition Multimedia Interface – usually digital video signal is transferred to analog television source which results in information loss; HDMI output can transfer digital video source without conversion to analog -> result is pure transfer of all video information (video and audio signals)

LCD (Liquid Crystal Display)
Display that consists of two polarizing transparent panels and liquid crystal surface sandwiched in between; voltage is applied to certain areas, causing crystal to turn dark; light source behind panel transmits through transparent crystals and is mostly blocked by dark crystals

Dolby Digital (DD)
Digital encoding system for audio signals that can be decoded by receiver or preamplifier with a DD decoder; often referred to as 5.1 channel surround system, because it compresses up to 5.1 discrete channels of audio (left front, center, right front, left surround, right surround, and low frequency effects) into one single bit stream

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Hometheatermag

Hometheater.about.com