AudioVidConcepts.com - Custom Home & Marine Theater Systems Installations & Designs

CALIBRATION
AUDIO VIDEO TERMINOLOGY

CALIBRATION [back to top]

Factory settings on TVs are almost always tweaked to maximum brightness and contrast and are enabled with image "edge enhancement" features as well. Manufacturers do this so that the TV picture will "pop" on the retail store floor compared to other models. However, this is not how the director of the programming you are viewing intended for you to see the film, or sports or sitcom that you see. It's not natural to the eye and a lot of the "enhancement" settings on a plasma or LCD TV these days are just the opposite of that. Setting the proper color, brightness, and and operating levels on an LCD TV can make a huge difference in your viewing pleasure.

WHY CALIBRATE?

If you're interested in getting the best possible picture from your flat panel or rear projection TV--or even a CRT tube TV--you can't assume that it comes straight out of the box with it's picture adjustments set properly. The next time you're in one of the "discount" home electronics stores, step back and take a look at the array of plasma, LCD, and projections TVs. Notice how they all look different? Since they're all displaying the same signal, shouldn't they all look the same?

The fact is, each manufacturer has a different idea about what "looks best," and they usually adjust their sets to show off their particular strengths--and hide their weaknesses. Also, pay attention to the lighting of the showroom itself: does your living room look like that when you watch movies, or even sports on TV? The pictures on the display floor may be "punchy" and bright, but the detail and resolution that gets washed out really takes away from your home theater experience. What's more, running a TV at these settings can even be damaging to the display technology, overloading pixel cells and projection lamps alike long before their time.

GETTING STARTED

The first step in calibrating your television lies in paying attention to your surroundings. Sit in the same spot you'd normally sit in to watch your TV. Then, make sure the lighting is at the same level you'll be using to watch movies: setting your TV to overcompensate for a brightly-lit room may give you distorted results. Watching in complete darkness may cause undue eyestrain, but a dim, diffuse light behind or to the side of your LCD TV is best. Just make sure to avoid any glare or reflection on the screen.

Next, be sure your display has "warmed up" for at least a half hour before attempting any calibration; this is to ensure that all the components of the display are at normal operating temperature and best approximate normal viewing conditions. You can take this time to familiarize yourself with the various display controls on your particular TV--get the manual out if you have to. The better you know which controls are available on your LCD TV, the better your end results will be. Though different manufacturers give different names to the controls, these are the levels you'll be adjusting:

Black Level, normally found on the Brightness control
White Level, usually called Contrast or Picture
Sharpness, or sometimes Detail
Color Saturation, usually labeled Color, or maybe Chroma
Color Tint, also known as Hue

Beyond these basic settings, many modern TVs come packed with so-called "picture enhancements" which in reality do nothing but spoil an otherwise accurate, lifelike picture. Take a moment to dig through your TVs menus and disable any of these "features." What you're looking for is anything labeled edge enhancement or detail enhancement, flesh tone or color "correction," etc. This is a broad generalization, but basically anything not listed in the five controls above can be safely turned off. Another thing to check for is often called a "Picture Mode," or something similar: in reviews, we often find best results from a Movie or Cinema mode, which usually gives the most accurate picture with the least "enhancement." A Normal mode is a safe bet when this isn't available, but definitely avoid anything called Vivid, Dynamic, or Sports mode. Sports mode may make the grass look nice and green, but unless you're watching The Masters, it's probably not that green in real life; Sports mode is just ruining the color.

On a similar note, have a look at the options available for your LCD TV's backlight settings. Like many of the settings, the backlight is probably set to its highest brightness, which is probably too bright for comfortable extended viewing, and shortens the lifespan of your LCD TV as well. Drop this setting down at least to it's "normal" value, or even try out the Low Power or Power Saver option if it's available (in dimly lit rooms).

Finally, a word about Color Temperature. Without getting into the rather complicated science behind it all, Color Temperature basically refers to the peak wavelength of a light source, which affects the color tint given to images which should be "pure" white. Suffice it to say that while most video is produced to what's called a "6500K Standard," (6500 degrees Kelvin), not every TV comes out of the box set to display that standard properly. In fact, factory settings are very rarely are set close to 6500K.

As an example, sunlight takes on a reddish tinge at sunset, when the sun's light is around 2000K, while "normal" average sunlight is 6500K. So what appears white in full sun will appear reddish at sunset. Similarly, your TV's color balance will be off if the color temperature isn't set properly. Even with professional instruments to measure the color temperature, there are few displays in any price range that can be perfectly calibrated to the 6500K standard, but your TV will have a selection that will be as close as you can get without accessing the professional service menu . The best way to tell is to use an "80% white" test image, and cycle through the Color Temperature settings on your TV until you find the achieve the most neutral gray possible. Again, names for the settings will vary, but Warm or Normal might be the best bet, with the gray tending towards reddish tones on the lower settings, and taking on a bluish or greenish cast on the High or Cool setting ("High" or "Low" refer to the color's wavelength, not the Color Temp.). If your TV happens to have a 6500K or 6500 setting, use that.

CALIBRATION TOOLS

Calibrating by sight alone might give you an improved picture from the factory settings, but to get the most detail and accuracy out of your LCD TV calibration, you're going to need a set of video test patterns. A cheap, easy fix is to use the THX Optimizer included on many DVD releases: just look for a DVD in your collection with the "THX Certified" logo. The THX Optimizer provides a usable set of patterns that will give recent results, but for a more thorough and accurate calibration, a dedicated Home Theater setup disc offers more fine-tuning options and the added benefit of step-by-step instructions that walk you through the entire process. Joe Kane's Digital Video Essentials disc and the AVIA Guide to Home Theater, published by Ovation Multimedia, are both highly-rated and effective choices. To get closer to D6500K than this, you will need to hire an ISF calibration specialist or use the settings in our reviews (if we've done one on your TV).

No matter which calibration disc you choose, the test patterns and adjustment process will be similar, following the five steps outlined above:

BLACK LEVEL

LCD and plasma TV manufacturers are proud of announcing their latest improvements in Contrast Ratio, and rightly so: the contrast of a display--that is, the difference between the "blackest" blacks and the "whitest" whites--is one of the most important factors in achieving a realistic picture that accurately conveys all the information present in a video signal. Half of that equation, the Black Level, will be calibrated using the Brightness control on your TV.

Black Level is optimized using a PLUGE pattern ('PLUGE' stands for Picture Line Up Generation Equipment), which regardless of your calibration disc will consist of a black-and-white screen divided into various shades of grays, running all the way down to black. A crucial step here is to make sure your DVD player itself is configured properly; the PLUGE pattern actually contains some areas which are below black, and you should make sure your DVD player is set up to send "below black" signals by enabling the option in the setup menu of your DVD player. Again, consult your manual if you can't find the setting: you're looking for "send below-black signals," "0 IRE Signals," or something similar.

The PLUGE test and Brightness calibration will basically take the form of lowering the TV's Brightness control until a black area of the screen (leftmost and rightmost black bars on Digital Video Essentials, dropshadow of the THX logo on the THX Optimizer) disappears from view, then slowly raising the Brightness until it is just visible. This adjustment assures that anything intended to be black on your DVD will be completely black, while still allowing you to see every detail in dark or shadowy scenes.

WHITE LEVEL

Closely related to the Black Level, but at the other end of the spectrum, is the White Level. Again, it's common for TVs to come out of the box with the Contrast or Picture control set far too high, which results in whites and bright shades "blooming," or bleeding together: think of the brightest shades in a scene looking as if they were "colored outside the lines." To adjust the White Level of your LCD TV, you will use a test pattern that features a pure white area contrasted with a 95% or near white area. The setup will differ according to which calibration disc you use, but the basic idea is the same. There are two things you're looking for in this adjustment: 1) You want to be able to distinguish the slightly darker box from the pure white box. This will ensure that you get all the fine details in a bright scene--like faint shadows or texture in snow, or the creases in an actor's white shirt. 2) You also want to ensure that the whites aren't set so high that the whites "bloom" into surrounding areas; this will greatly reduce the contrast and sharpness of your picture as colors bleed into one another.

To make the adjustment, first raise the Contrast control (sometimes called Picture) until the darker white area disappears into the pure white. Then, gradually decrease the Contrast until the box is visible again. One click may make the difference, so take your time and make careful adjustments. Finally, once you have the White Level where you want it, closely examine the edges of the pure white area where it borders the black background. Is it a sharp line, or does the white area blur or smear into the black? If it's a sharp line, you're in business. If the white area "blooms" into the black, back off the Contrast a notch or two until the border is sharply-defined.

Because the Brightness and Contrast settings are so closely related, you may find in some cases that setting the proper White Level disturbs your setting of the Black Level (Brightness control). After setting the Contrast or Picture properly, go back and have another look at the PLUGE pattern and double-check the Black Level setting. If you're very picky, or your TV lacks fine adjustments in the Brightness and Contrast controls, you may have to go back and forth a couple of times to be sure everything's in order.

SHARPNESS

Sharpness is perhaps the most difficult element of TV calibration to explain, in part because it has more to do with how our eyes perceive an image than with anything that can be physically measured. For starters, it may help to understand what the Sharpness control can and cannot do. It cannot actually increase or decrease the physical resolution of your television: the resolution depends on the actual number of pixels available in the panel's construction. What it can do, though, is make transitions between colors and shades appear sharper to the eye. You might initially think "the sharper the better," and set the Sharpness to it's maximum. The problem is, however, that as your TV increases the visible sharpness of an image, it also introduces unwanted artifacts that detract from accuracy, and even cause eyestrain during prolonged viewing.

The THX Optimizer does not include a Sharpness test pattern, but the DVE and AVIA discs include similar ones: a gray background featuring a black circle with lines radiating out towards the edges of the screen. This pattern is designed to give the sharpness of your TV an optimal test, but even without a test pattern you can see the effects of the Sharpness control: when the Sharpness setting exceeds the optimal level, you will see the artifacts of excessive sharpness around any edge between black and white, or between different colors on the screen. This usually appears as a either a dark "ghost" images of the edge, or a bright "halo" around objects in the picture. These artifacts, not present in the DVD signal, serve to highlight the edges and make appear more defined to the eye.

What you're looking for as you adjust the Sharpness is to get the sharpest possible lines and text in the test pattern image, without the appearance of these false edges and the "halo" effect. Start by cranking up the Sharpness control until the halo artifacts are evident, then back down slowly to the point where they just disappear. At first glance, the picture may appear to the eye to be overly "soft," or slightly blurry. But once your eyes get used to the Sharpness level, you'll actually begin to see more detail, especially in moving images, because the edge effects won't be distracting you from the intended image.

As with any setting, of course the final choice is up to you: some TVs, even good ones, have a naturally soft picture and you may find you actually like a little "extra" sharpening to get the most enjoyable effect. If nothing else, calibrating the Sharpness by this method will give a good baseline to start from.

COLOR SATURATION AND TINT

The Color adjustments are where having the proper calibration equipment can make all the difference in the world. Both the AVIA Guide to Home Theater and the Digital Video Essentials discs come packaged with blue, red, and green plastic films that accompany this part of the calibration. THX offers a set of blue filter glasses, which you can order through the THX website. The THX Optimizer combines Color and Tint on the same test, and the more sophisticated discs offer a couple of choices for color and tint tests.

Some of the language about Color adjustment, sometimes called Color Saturation, can be a bit hard to follow, but it all boils down to this: there is a level on your TV where the monitor is displaying precisely the color information sent to it by the DVD player, no more no less. That's the level you're looking for. Your TV probably comes out of the box set to artificially boost the color levels, which makes for a dramatic appearance on the sales floor, but ultimately is a distorted version of what the movie director intends you to see. Again, make doubly sure that your TV is in the most neutral color "mode" before undertaking this potion of the calibration: Vivid, Sports, or other modes are designed to artificially boost color saturation in different spectra, and may throw off your calibration considerably.

To set the Color or Saturation level, you'll hold the blue-tinted filter in front of your eyes and adjust the Color control on your TV until the appropriate boxes match. Test patterns vary among calibration discs, so make sure you understand the directions for your particular system. Once you have the color saturation set to the most accurate level, you can move on to the Tint.

Color Tint, labeled Hue on some TVs, basically controls the balance of Red, Green, and Blue in your TV's picture. Following the instructions on your test disc, adjust the Tint control appropriately. Also, be aware that, just like the Brightness and Contrast controls, Color and Tint are to some degree dependent upon each other. After setting the Tint appropriately, you may want to go back and check the Color level just to be sure. Once you're satisfied, you're ready for one final step in color calibration: do you like what you see?

Just like Sharpness, color levels are to some extent largely a matter of taste. Before you call your TV calibration complete, use the scenes provided on your test disc, or a favorite DVD, to double-check your color and hue settings. Of course you'll want to use a scene where you know beforehand what the colors should look like! Find a standard color you know, like a US Flag or your favorite sports team's uniform, and fine-tune the Color and Tint settings until it looks "right" to your eye. The ultimate test for color saturation and tint is flesh tones. Complexions vary widely of course, but if everyone looks badly sunburned, or more Martian than human, back off the Color control and/or tweak the Tint accordingly.

WHAT YOU SEE IS WHAT YOU GET

You might say the main consideration in TV calibration is found in the Black Level and White Level adjustments: setting these properly will make sure you get everything you paid for out of the contrast of your TV, while possibly improving its lifespan by not overdriving it's pixels or lamps. In terms of pure accuracy, adjusting the color levels and sharpness as recommended will make sure that what you see on your screen is what the move director intended you to see. Of course, surrounding room light conditions will determine a lot about how the LCD looks, and when all is said and done, it's your TV, and you can watch it how you like it. Think the picture's too "soft"? Bump up the Sharpness a bit. Not enough detail in dark scenes, Turn up the Brightness. And if you want green, green grass--even at Lambeau Field in mid November--then by all means, crank up that Sports mode and go crazy with the Color control--just don't be shocked when your friends ask "What's wrong with your TV?"

AUDIO VIDEO TERMINOLOGY [back to top]

100 Base-T:
100 Base-T is an Ethernet transmission standard. The "T" stands for unshielded twisted-pair wire, or UTP.RJ 45 and RJ11 telephone jacks and four pair UTP telephone wire are specified for interconnecting nodes to the LAN. It operates at a transmission rate of 100Mbps.

1080i vs 1080p
There has been a lot of concern and confusion over the difference between 1080i and 1080p. This stems from the inability of many TVs to accept 1080p. To make matters worse, the help lines at many of the TV manufacturers (that means you, Sony), are telling people that their newly-bought 1080p displays are really 1080i. They are idiots, so let me say this in big bold print, as far as movies are concerned THERE IS NO DIFFERENCE BETWEEN 1080i AND 1080p. See, I did it in caps too, so it must be true. Let me explain (if your eyes glaze over, the short version is at the end).

For clarification, let me start by saying that there are essentially no 1080i TVs anymore. Unless you bought a CRT based TV, every modern TV is progressive scan (as in LCD, Plasma, LCOS, DLP). They are incapable of displaying a 1080i signal as 1080i. So what we’re talking about here mostly applies to people with 1080p native displays.

Movies and almost all TV shows are shot at 24 frames-per-second (either on film or on 24fps HD cameras). All TVs have a refresh rate of 60Hz. What this means is that the screen refreshes 60 times a second. In order to display something that is 24fps on something that is essentially 60fps, you need to make up, or create new frames. This is done using a method called 3:2 pulldown (or more accurately 2:3 pulldown). The first frame of film is doubled, the second frame of film is tripled, the third frame of film is doubled and so on, creating a 2,3,2,3,2,3,2 sequence. It basically looks like this: 1a,1b,2a,2b,2c,3a,3b,4a… Each number is the original film frame. This lovely piece of math allows the 24fps film to be converted to be displayed on 60Hz products (nearly every TV in the US, ever).

This can be done in a number of places. With DVDs, it was all done in the player. With HD DVD, it is done in the player to output 1080i. With Blu-ray, there are a few options. The first player, the Samsung, added the 3:2 to the signal, interlaced it, and then output that (1080i) or de-interlaced the same signal and output that (1080p). In this case, the only difference between 1080i and 1080p is where the de-interlacing is done. If you send 1080i, the TV de-interlaces it to 1080p. If you send your TV the 1080p signal, the player is de-interlacing the signal. As long as your TV is de-interlacing the 1080i correctly, then there is no difference. Check out this article for more info on that.

The next Blu-ray players (from Pioneer and the like) will have an additional option. They will be able to output the 1080p/24 from the disc directly. At first you may think that if your TV doesn't accept 1080p, you'll miss out on being able to see the "unmolested" 1080p/24 from the disc. Well even if your TV could accept the 1080p/24, your TV would still have to add the 3:2 pulldown itself (the TV is still 60Hz). So you're not seeing the 1080p/24 regardless.

The only exception to that rule is if you can change the refresh on the TV. Pioneer's plasmas can be set to refresh at 72 Hz. These will take the 1080p/24, and do a simple 3:3 pull down (repeating each frame 3 times).

Short Version

What this all means is this:

When it comes to movies (as in HD DVD and Blu-ray) there will be no visible difference between the 1080i signal and the 1080p signal, as long as your TV correctly de-interlaces 1080i. So even if you could input 1080p, you wouldn't see a difference (because there is none).
There is no additional or new information in a 1080p signal from movie based content.
The only time you would see a difference is if you have native 1080p/60 content, which at this point would only come from a PC and maybe the PS3. 1080p/60 does have more information than 1080i/30, but unless you're a gamer you will probably never see native 1080p/60 content. It is incredibly unlikely that they will ever broadcast 1080p (too much bandwidth) or that 1080p/60 content will show up on discs (too much storage space and no one is using it to record/film).

So all of you people who bought 1080p displays only to be told by the companies that you had bought 1080i TVs, relax. The TV will convert everything to 1080p. Now if you bought a TV that doesn't de-interlace 1080i correctly, well, that's a whole other story.

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.