Anamorphic:
The DVD format is specially designed to support widescreen displays. Widescreen 16:9 video can be stored on the DVD disc in anamorphic form, meaning the picture is squeezed horizontally to fit the standard 4:3 rectangle, and then unsqueezed during playback.

This anamorphic squeezing results in less of the picture being wasted on the black letterbox mattes. DVD has a frame size designed for 1.33 display, so the video still has to be made to fit, but because it's only squeezed horizontally, 33% more pixels (25% of the total pixels in a video frame) are used to store active picture instead of black. Anamorphic video is best displayed on widescreen equipment, which stretches the video back out to its original width.

Anamorphic video can be converted by the player for display on standard 4:3 TVs in letterbox or pan & scan form. If anamorphic video is shown unchanged on a standard 4:3 display, people will look tall and skinny as if they have been on a crash diet. The setup options of DVD players allow the viewer to indicate whether they have a 16:9 or 4:3 TV.

Aspect ratio:
The ratio between the horizontal measurement and vertical measurement of a TV screen. Standard NTSC televisions are built with a 4:3 aspect ration, while HDTV systems are built to a 16:9 ratio. Keep in mind however, that not all theatrical movies are filmed in 16:9 (or 1.78 aspect ratio). Many movies are filmed in 1:85, 2.15 or 2.35 widescreen. Movies filmed in an aspect ratio greater than 16:9 will result in black bars on the tops and bottom of the screen on a widescreen television. The higher the ratio, the wider (relatively) the screen.

Attenuation:
The loss of signal power during transmission. Usually a concern when a signal is transmitted over a long distance.

AWG (American Wire Gauge):
Measurement of the diameter of a wire or cable. Gauge is a unit used to measure wire thickness. The smaller the number, the thicker the wire. (i.e. 10 gauge wire is much thicker than 16 gauge wire). Typically, is it desirable to have the lowest gauge speaker wire possible. Around 12 gauge is ideal, above 16 gauge is not recommended for serious home theater applications.

Bandwidth:
The transmission capacity of a cable or other media. Usually measured in bits per second or in cycles per second (hertz). A common analogy to bandwidth is a water pipe the bigger the pipe (bandwidth) the more water that can flow through it per unit of time.

Bi-Polar, Bi-Pole (Speaker):
Bi-polar refers to speakers with drivers that are fired in two different directions, but are in phase causing an increase in bass output. I this type of speaker the drivers can be in the front and back of the speaker, side firing, or at 90º angles from one another. There are also speakers which function as both bipolar and dipolar. This can be adjusted using a switch.

Bi-Wiring:
Bi-wiring refers to separate wire runs from a common amplifier output to two different inputs on the same speaker. This requires a speaker specifically designed with bi-wiring in mind as the speaker's passive crossover must be designed to allow this. And the speakers must have two sets of external binding posts connected by removable jumpers or "bus bars."

Bps (bits per second):
A measurement of bandwidth. This is the number of data bits that can be carried over a network in a second. Often measured in thousands of bits per second (kilobits per second Kbps) or millions of bits per second (megabits per second Mbps).

Broadband:
A method of transmitting signals where several data signals are modulated onto different frequencies and carried on the same cable or network medium. Compare with baseband.

Cable modem:
A high-speed Internet access device that uses the coaxial cable network of cable television providers to connect a home PC or LAN to the Internet over frequencies unused by television services.

Category 5:
(CAT-5): A performance rating for UTP wiring that is suitable for telephone and Ethernet networks up to 100 Mbps, as well as ATM data networks up to 155 Mbps. See also UTP.

CCTV:
Closed-circuit TV, an in-home video surveillance network.

Coaxial cable:
Shielded cable that you can use to carry television signals or data within a network. Coaxial cable typically consists of a center conductor, a layer of insulation, another conductor wrapped around the insulation, and an outer layer of shielding and jacketing. Coaxial cables used in home video applications are designed with a 75 ohm impedance, and are rated according to their bandwidth capacity. The most commonly found coaxial cables are RG-59 and RG6.

Composite Video:
The baseband video signal output of a VCR, DVD player, or other video source component Composite video utilizes one (RCA-jack type) cord to transmit all picture information.

Component Video:
A video transmission method. Better than composite video and s-video, equal to RGB video. Component video uses three (RCA-jack type) cables to distribute the red, blue and green portions of a video transmission separately. Component video is typically used with DVD players and HDTV systems.

Conduit:
A plastic or metal pipe that is used to contain cable runs. It is often installed empty into new homes to allow easy running of new cables in the future.

Crossover:
A crossover is a system of filters designed to divide audio bandwidth between each individual driver in each individual speaker.

dB (Decibel):
A dB is a unit of measure of signal strength, usually the relation between a transmitted signal and a standard signal source. Every 3 dB = 50% of signal strength, so therefore a 6 dB loss = a loss of 75% of total signal strength.

Demarcation Point:
The point of interconnection between telephone company facilities and your home wiring. The demarcation point ("demark") shall be located on the subscriber's side of the telephone company's protector, or the equivalent thereof in cases where a protector is not required. In most cases this point also delineates the responsibility for the network. Everything inside of the demarcation point is usually the responsibility of the homeowner.

Digital subscriber line (DSL):
A new data-connection method that allows high-speed Internet connections and other network connections over a standard telephone line. Variants of DSL, such as asymmetric digital subscriber lines, are identified by a preceding initial (ADSL in this case).

Dipolar, Dipole (Speaker):
Dipolar refers to speakers with drivers that are fired in two different directions and are in reverse phase causing a cancellation of sound waves in front of the speaker. This is usually done in rear speakers that are wall mounted. The front of the speaker is aimed at the listening area, which causes all of the sound to bounce off the walls before it is heard. This makes it almost impossible to determine where the speaker is, creating a true surround effect.

Distribution panel:
In a video network, this is the panel that concentrates all broadband video signals from antennas, cable TV feeds, and in-home video sources and distributes them to outlets throughout the house. Often it also includes a built-in signal amplifier.

Dolby Digital:
Dolby Digital (AC-3) is an advanced perceptual coding technology for transmission and storage of up to five full-range channels, plus a supplemental bass-only effects channel (referred to as a .1 channel due to the smaller number of bits needed for the information), in less space than is required for one linear PCM coded channel on a compact disc. Dolby Digital is a more powerful and flexible coding system than AC-2 and provides a feature set including -- 1) down mixing for optimal reproduction in mono, stereo, and Pro Logic compatible configurations as well as full 5.1 channel sound; 2) carriage of dynamic range and dialog level control information to decoders; and 3) operation over a wide range of bit rates. Dolby Digital is being used on the audio tracks on DVD, and is the audio standard on the new high definition television (HDTV) system which went into operation in the United States in 1998.

Dolby Digital EX:
Dolby Digital Surround EX adds a center rear surround channel to the 5.1-channel format, providing a new tool for delivering greater sonic reality and excitement to the audience.

DSP Digital Signal Processor:
These are audio effects added on-the-fly to sounds by a receiver or amplifier. They usually consist of echo and reverb effects labeled "jazz, theater, hall, etc."

DSS Direct Satellite System:
A DSS system will use at least one small satellite dish (either 18" round or 24" oval) and a receiver with a removable access card (similar to the size of a credit card). DSS systems provide you with hundreds of channels to choose from. And because the signals are all digital, DSS systems are capable of delivering high quality video and CD quality audio. With the right equipment, it is also possible to receive HDTV signals over satellite.

DTS:
Digital Theater Systems is an international, digital technology company specializing in multi-channel audio for entertainment. Founded in 1993, DTS quickly became the leading provider of premium, discrete, multi-channel audio. DTS Digital Surround is an encode/decode system that delivers six channels (5.1) of master-quality, 20-bit audio. In the encoding process, the DTS algorithm encrypts six channels of 20-bit digital audio information in the space previously allotted for only two channels of 16-bit linear PCM. Then during playback, the DTS decoder reconstructs the original six channels of 20-bit digital audio. Each of these six channels is audibly superior to the 16-bit linear PCM audio found on conventional compact discs.

DTS-ES:
The new DTS-ES discrete 6.1 format employs a new, proprietary technology for the playback of discrete, 6.1-channel content from DVDs and CDs. The additional channel over 5.1 audio is a rear center channel. In addition to DTS-ES discrete 6.1 decoding, the new DTS-ES program includes the introduction of the DTS-ES Matrix 6.1 surround decoding format, which offers backward compatibility with existing ES matrix-encoded content, and DTS Neo:6, which is a matrix technology that derives up to 6.1-channel playback from conventional, stereo program material.

DVD-Audio:
A high-fidelity audio storage medium with flexibility in the numbers of channels, sampling frequencies, wordlengths and other features such as video elements; DVD-Universal players can play both DVD-Video and DVD-Audio discs.

DTV (digital television):
Digital Television. DTV is composed of three separate standards: HDTV 1080i (1080 lines of resolution, 16:9 aspect ratio); HDTV 720p (720 lines of resolution, 16:9 aspect ratio); and SDTV (480 lines of resolution, 16:9 or 4:3 aspect ratio)

The U.S. Congress has mandated a change from the current NTSC (analog) television broadcasting standard to DTV (digital) broadcasting. The Federal Communications Commission has established a schedule for the introduction of DTV. Most Americans are scheduled to have access to DTV by 1999 and everyone in this country is scheduled to have DTV access by the year 2002. At the end of the transition period -- which is now scheduled for December 31, 2006 -- broadcasters will be required to surrender their analog channels to the federal government. This will be the end of standard NTSC broadcasts.

DVD:
Digital Video Disc or Digital Versital Disc. DVD has the same physical dimensions of a CD; however it can hold much more information. DVD aims to encompass home entertainment, computers, and business information with a single digital format, eventually replacing audio CD, videotape, laserdisc, CD-ROM, and perhaps even video game cartridges. DVD has widespread support from all major electronics companies, all major computer hardware companies, and all major movie and music studios. With this unprecedented support, DVD has become the most successful consumer electronics product of all time in less than three years of its introduction.

Some features of DVD include: Up to 8 hours of high-quality digital video on one disc, support for both widescreen and standard formats on the same disc, up to 8 tracks of multi-channel digital audio (for multiple languages, DVS, etc.), up to 32 subtitle/karaoke tracks, automatic "seamless" branching of video (for multiple story lines or ratings on one disc), up to 9 camera angles (different viewpoints can be selected during playback), menus and simple interactive features (for games, quizzes, etc.) and much more.

DVI:
Digital Visual Interface. A data transmission port which supports up to 5 Gigabits/sec speed. Bandwidth of 2.2 Gigabits/sec. is required to support uncompressed HD video transmission. With bandwidth of up to 5 Gbps for a single DVI link, compared to the 400 Megabits/sec. supported by IEEE 1394, DVI is the only digital interface capable of accommodating uncompressed digital data such as HD video. DVI also has the bandwidth to support higher audio fidelity, such as more channels of surround sound or 96 KHz sampling rates, as well as higher video resolution such as 1080p-ensuring no risk of long-term obsolescence.

Ethernet:
A local area network (LAN) used for connecting computers, printers, workstations, servers, terminals, etc within the same building or campus. It operates over twisted wire or coaxial cable the theoretical limit for Ethernet, measured in 64 byte pockets, is 14,800 packets per second (PPS). By comparison, Token Ring is 30,000. Ethernet specifies a CSMA/CD (Carrier Sense Multiple Access with Collision Detection). The most common variation of Ethernet found in home networks is the 10 Mbps lOBase-T variant, but dozens of other variations exist with speeds up to 1000 Mbps.

FireWire:
A new high-speed data communications protocol most often used for connecting digital video systems to computers. Future uses are envisioned to expand the role of FireWire to include whole-home data, video, and audio networks. Also known as IEEE 1394.

HDTV High-Definition Television. It is the most life-like picture you can get with the sole exception of looking out a window. HDTV offers wider pictures with greater detail and the clarity of motion pictures. Compared to standard television (NTSC), the true HDTV image has twice the luminance definition - vertically and horizontally - and is twenty-five percent wider. Standard television aspect ratio is 4:3 - the HDTV aspect ratio is 16:9. The 16:9 ratio is much closer to the average widescreen image shown in movie theaters. However, the biggest difference between NTSC and HDTV is its clarity. True HDTV pictures are composed of 1080 active lines (1125 total whereas current standard television pictures are composed of only 480 active lines (525 total). The lines that make up standard television pictures are clearly visible, but HDTV lines are not at all noticeable. The fine-grained HD picture contains five times more information than does the standard television picture and is accompanied by multi-channel, Dolby Digital audio.

Home Phoneline Networking Association (HomePNA):
An adaptor that converts computer data to transmit over standard telephone lines.

Impedance:
Resistance to the flow of current in an alternating current circuit measured in ohms. Most speakers have an 8 ohm impedance rating.

Infrared (IR):
The part of the light spectrum just below the visible portion. Often used for wireless networked devices and remote controls in a home.

Interconnects:
Interconnects are a generic term for all of the audio and video cables that connect your system together. Cables are not accessories but components, as critical to your system's performance as your speakers or monitor.

LAN (local area network):
A computer data communications network used within a limited physical location, like a house. Most home LANs utilize the Ethernet protocol.

LFE:
Low Frequency Effects. These are the very deep booming bass sounds recorded into a Dolby Digital or DTS audio track. They are typically reproduced by the subwoofer in your home theater speaker system, however if a subwoofer is not present in the system, most receivers will attempt to reproduce these sounds through your main front speakers. Because it is not essential to the soundtrack, the LFE track is identified as the ".1" in a 5.1 digital audio recording. Soundtracks recorded as 5.0 Dolby Digital do not include a LFE track.

Lines of Horizontal Resolution:
Lines of horizontal resolution are often confused with scan lines. The two are totally different things, be careful when shopping for equipment. Lines of horizontal resolution refer to visually resolvable vertical lines per picture height. In other words, it's measured by counting the number of vertical black and white lines that can be distinguished an area that is as wide as the picture is high. Lines of horizontal resolution applies both to television displays and to signal formats such as that produced by a DVD player. Since DVD has 720 horizontal pixels (on both NTSC and PAL discs), the horizontal resolution can be calculated by dividing 720 by 1.33 (for a 4:3 aspect ratio) to get 540 lines. On a 1.78 (16:9) display, you get 405 lines. In practice, most DVD players provide about 500 lines instead of 540 because of filtering and low-quality digital-to-analog converters. VHS has about 230 (172 widescreen) lines, broadcast TV has about 330 (248 widescreen), and laserdisc has about 425 (318 widescreen). Scan lines, on the other hand, measure resolution along the y axis. DVD produces 480 scan lines of active picture for NTSC and 576 for PAL. The NTSC standard has 525 total scan lines, but only 480 to 483 or so are visible. (The extra lines are black and are encoded with other information). Since all video formats (VHS, LD, broadcast, etc.) have the same number of scan lines, it's the horizontal resolution that makes the big difference in picture quality.

LNB:
Low Noise Block filter. The LNB receives the signals bouncing off the satellite dish collector.

Modem:
A device that converts a computer's digital signals into analog tones that can be carried over a telephone network. The name comes from the function, which is to MODulate and DEModulate these signals.

Modulate:
The process of changing the electrical properties (such as frequency) of an signal to facilitate carrying it over a network. Signals are often modulated to different frequencies to allow multiple signals to be carried over a single cable.

Network Interface Card (NIC):
A device that connects to an internal bus in a PC, which provides an interface between the computer and the LAN.

NTSC:
National Television System Committee. In 1953 the NTSC devised the NTSC television broadcast system. NTSC is also commonly used to refer to one type of television signal that can be recorded on various tape formats such as VHS.

The NTSC standard has a fixed vertical resolution of 525 horizontal lines stacked on top of each other, with varying amounts of "lines" making up the horizontal resolution, depending on the electronics and formats involved. There are 59.94 fields displayed per second. A field is a set of even lines, or odd lines. The odd and even fields are displayed sequentially, thus interlacing the full frame. One full frame, therefore, is made of two interlaced fields, and is displayed about every 1/30 of a second.

Ohm:
Ohm is the unit used to measure the resistance presented by a loudspeaker when it is introduced a signal by an amplifier. (The word Ohm comes from German physicist Georg Simon Ohm, 1787-1854). Conventional wisdom makes an 8 ohm loudspeaker load the most acceptable because it "protects" the amplifier from delivering too much current. A 4 ohm loudspeaker can encourage a marginally designed amplifier to deliver more current than it comfortably can. All speakers in your home theater system should have the same Ohm rating.

Patch panel:
A device that allows the interconnection of home runs of data or phone cabling at a central distribution point.

PCM:
Pulse Code Modulation. PCM is a digital scheme for transmitting analog data. The signals in PCM are binary; that is, there are only two possible states, represented by logic 1 (high) and logic 0 (low). This is true no matter how complex the analog waveform happens to be. Using PCM, it is possible to digitize all forms of analog data, including full-motion video, voices, music, etc.

Pink Noise:
Pink noise is noise that has equal energy in each octave.

Protocol:
A common language or specification used by devices communicating over a network.

Punchdown:
A method for securing cables in a patch panel or outlet. The wire is placed over a metal clip, and then punched down (with the appropriately named punchdown tool) to penetrate the wire's insulation and provide an airtight contact.

RF (radio frequency):
The segment of the electromagnetic spectrum below visible light, used for both wireless transmission of data and for transmitting modulated signals over cable.

RG 6:
A type of coaxial cable with an 18-gauge center conductor. It may be dual-shielded, which means it has a layer of foil and a layer of braid, or quad-shield, which means it has a second layer of foil and another layer of braid on top of the second foil layer. RG-6 can carry signals up to 2GHz. Satellite systems typically use signals in the range of 950MHz to 1.5GHz.

RGB:
A video transmission method. A video transmission method. Better than composite video and s-video, equal to component video. RGB video uses one 15 pin video cable (this is the same video cable and distribution method used in computer monitors) to distribute the video signal. Aside for PC's, RGB video is typically found on HDTV and DBS satellite systems.

RJ-11:
A six conductor modular jack that is typically wired for four conductors. It is the most common telephone jack in the world.

RJ-45:
The standard eight-position modular jack used in data networks. SACD (Super Audio Compact Disc) A standard for high-density storage of two-channel CD and two-channel and multi-channel SACD audio recordings. SACD recordings use 1-bit Direct Stream Digital (DSD) coding.

Shielding:
A protective layer in a cable that prevents electromagnetic interference from outside sources.

Splitter/combiner:
A device used in coaxial video networks either to split a single cable's signal onto several cables or to combine the signals from several cables onto a single one. When used to split signals, a splitter/combiner introduces a certain amount of attenuation to the signal (usually listed on the splitter).

Structured Wiring:
Structured Wiring is the backbone of a true high-speed connected home. It contains two CAT 5e and two RG6 quad shield cables that run from every room to a central location in the house. This enables the homeowner to connect high-speed internet, satellite, cable TV, phone, fax, control, video, and network all the PC's in the house, in every room in the house.

S-VHS:
Super VHS. Better than standard VHS, not as good as DVD. An S-VHS recorder will allow you to record programs in up to 480 lines of resolution (a standard VHS will only record/play 240 lines of resolution. S-VHS VCRs will allow you to play standard VHS tapes. Also, a Super-VHS VCR will have at least one S-Video output & input.

S-Video
A video transmission method. Better than composite video, not as good as component video. S-video separates luminance (black and white information) and chrominance (color information) signals. An s-video cord slightly resembles a computer PS-2 cable.

Subwoofer:
A subwoofer is a (usually powered) speaker which produces very deep booming bass sounds. Subwoofers are responsible for reproducing the LFE track in a 5.1 Dolby Digital or DTS soundtrack. They are typically a cube shape with a large single woofer either pointing directly at the ground or directly at the listener. Usually, subwoofers are placed in the corner of the room. Ideally, a subwoofer should be placed where it is impossible to determine the direction of where the sound is coming from.

Surge suppressor:
A device that prevents damage to electrical or electronic equipment by isolating it from unexpected rises in current or voltage (like lighting strikes).

THX Surround EX:
Establishing a new benchmark for multi-channel sound, Lucasfilm THX has announced THX Surround EX a home theatre application of the cinema surround sound technology that made its theatrical debut with the opening of Star Wars: Episode I The Phantom Menace. THX Surround EX is an enhancement to digital sound that decodes a back surround channel in a film soundtrack allowing for dramatic 360° surround sound effects that are smoother and more accurately placed either directly behind or directly beside a viewer.

Twisted pair:
Cabling, most often used for telephone and data networks, in which individual pairs of wire are twisted around each other to reduce electrical interference. See also UTP.

Universal remote control:
An IR or RF remote control that can be programmed to control multiple devices. A "learning" universal remote control can be taught control signals from just about any other remote.

White Noise:
Noise that has equal energy at each frequency.

Widescreen:
A television with an aspect ratio of 16:9.

YPbPr:
Another term for component video.