Hardware based on Intel HD Audio specifications is capable of delivering 192 kHz/32-bit quality for two channels, and 96 kHz/32-bit for up to eight channels. However, as of 2008, most audio hardware manufacturers do not implement the full high-end specification, especially 32-bit sampling resolution.

Intel Mainboard (D915PGN)

Microsoft Windows Vista and Windows XP SP3 include a Universal Audio Architecture (UAA) class driver which supports audio devices built to the HD Audio specification. Mac OS X has full support with its AppleHDA driver. Linux also supports Intel HDA controllers, as do the OpenSolaris, FreeBSD, NetBSD and OpenBSD operating systems.

Like AC97, HD Audio is a specification that defines the architecture, link frame format, and programming interfaces used by the controller on the PCI bus and by the codec on the other side of the link. Implementations of the host controller are available from Intel, NVidia, AMD, and possibly others. Codecs which can be used with such controllers are available from many companies, including Realtek, Conexant, and Analog Devices.

Extracts six audio channels and one low-frequency channel from either a specially encoded two-channel or stereo source. Expands a back surround channel from a 5.1 channel source:

• Two channels for speakers at the front-left (L) and right (R).
• One channel for speaker at the centre-centre (C).
• Two channels for surround speakers at the sides-side left (LS) and side right (RS).
• One channel for surround speakers at the rear-back surround channel (BS).
• One low-frequency channel to drive a sub-woofer.

Placement: The front speakers should be placed at the edges of the screen, toed in to face the central listening location. The centre speaker should be placed behind the screen (when using projection) or over or under a television. Side channel speakers should be placed to the left and right of the listening position, equidistant from the front speakers and the rear speakers. Rear channel speakers should be placed slightly behind the listening position, and should have a normal high-quality monopolar construction. Front speakers should be at ear height and surrounds should be above.

6.1-7.1 Channel Surround (Dolby Digital EX)

Delivers five audio channels, one extracted audio channel and one LFE channel from a six channel source:

• Two discrete channels for speakers at the front-left (L) and right (R).
• One discrete channel for speaker at the centre-centre (C).
• Two channels for surround speakers at the sides-left surround (LS) and right surround (RS). The discrete LS and RS channels are dematrixed into LS, RS, and back surround (BS).
• One channel for surround speakers at the rear-back surround channel (BS). The back surround channel can be made into two channels by the receiver.
• One low-frequency effects channel (LFE).

Placement: The front speakers should be placed at the edges of the screen, toed in to face the central listening location. The centre speaker should be placed behind the screen (when using projection) or over or under a television. Side channel speakers should be placed to the left and right of the listening position, equidistant from the front speakers and the rear speakers. Rear channel speakers should be placed slightly behind the listening position, and should have a normal high-quality monopolar construction. Front speakers should be at ear height and surrounds should be above ear height.

7.1 Channel Surround (Dolby Digital Plus, DTS-HD, Dolby TrueHD)

Delivers seven audio channels and one LFE channel from an 8 channel source:

• Two channels for speakers at the front-left (L) and right (R).
• One channel for speaker at the centre-centre (C).
• Two channels for surround speakers at the sides-left surround (LS) and right surround (RS).
• Two channels for surround speakers at the rear-left back (LB) and right back (RB).
• One low-frequency effects channel (LFE).
• Describes the Dolby Digital Plus discrete Surround system. Source media, usually Blu-Ray and sometimes HD DVD is often branded with “Dolby Digital Plus” and/or “DTS-HD” logos.

Placement: The front speakers should be placed at the edges of the screen, toed in to face the central listening location, and the tweeters should be ear height. The centre speaker should be placed behind the screen (when using projection) or over or under a television, and as close to ear height as possible. Side channel speakers should be placed on side walls, to the left and right of the listening position, equidistant from the front speakers and the rear speakers. Rear channel speakers should be placed on side walls, slightly behind the listening position, and should have a normal high-quality monopolar construction. Front speakers should be at ear height and surrounds should be above ear height.

10.2 Channel Surround

10.2 is the surround sound format developed by THX creator Tomlinson Holman of TMH Labs and University of Southern California (schools of Cinema/Television and Engineering). Developed along with Chris Kyriakakis of the USC Viterbi School of Engineering, 10.2 refers to the format’s promotional slogan: “Twice as good as 5.1″. Advocates of 10.2 argue that it is the audio equivalent of IMAX. 10.2 augments the LS (left surround) and RS (right surround) channels by two point surround channels that can more finely manipulate sound-allowing the mixer to shift sounds in a distinct 360° circle around the movie watcher.

The 14 discrete channels are:

• Five front speakers: Left Wide, Left, Centre, Right and Right Wide
• Five surround channels: Left Surround Diffuse, Left Surround Direct, Back Surround, Right Surround Diffuse and Right Surround Direct
• Two LFE channels: LFE Left, LFE Right
• Two Height channels: Left Height, Right Height

The .2 of the 10.2 refers to the addition of a second subwoofer. The system is bass managed such that all the speakers on the left side use the left sub and all the speakers on the right use the right sub. The Centre and Back Surround speaker are split among the two subs. The two subs also serve as two discrete LFE (Low Frequency Effects) channels. Although low frequencies are not localizable, it was found that splitting the bass on either side of the audience increases the sense of envelopment.

22.2 Channel Surround

22.2 is the surround sound component of Ultra High Definition Video (Super Hi-vision television with 4320 scanning lines), and has been developed by NHK Science & Technical Research Laboratories. As its name suggests, it uses 24 speakers. These are arranged in three layers: A middle layer of ten speakers, an upper layer of nine speakers, and a lower layer of three speakers and two sub-woofers. The system was demonstrated at Expo 2005, Aichi, Japan, the NAB 2006 conference, Las Vegas, and at IBC 2006 and IBC 2008, Amsterdam, Netherlands.

3.0 Channel Surround (Dolby Surround)

Three audio channels are produced from a specially encoded two-channel source:

• Two channels for speakers at the front-left (L) and right (R).
• One channel for surround speaker or speakers at the rear-surround (S).

Placement: Three identical speakers placed equidistant around a central listening position. If two rear speakers are used they should also be placed above ear height, slightly behind the listening position, and should be of bi-polar construction.

4.0 Channel Surround (Quadraphonic)

Four audio channels are produced either from a specially encoded two-channel source or a four-channel source:

• Two channels for speakers at the front-left (L) and right (R).
• Two channels for surround speakers at the rear-surround left (LS) and surround right (RS). Some newer receivers support the LFE channel.

Placement: Quadraphonics is a system designed for music only. All speakers should be at an ±45˚. All speakers should be above ear height.

5.1 Channel Surround (3-2 Stereo) (Dolby Pro Logic II)

Five audio channels are produced either from a specially encoded two-channel or a stereo source:

• Two channels for speakers at the front-left (L) and right (R).
• One channel for speaker at the centre-centre (C).
• Two channels for surround speakers at the rear-surround left (LS) and surround right (RS).
• One low-frequency effects channel (LFE).

Placement: 5.1 speaker layouts should conform to the ITU-R BS.775 standard, despite the myth that music and video content require different placements. The ITU standard states that the left and right speakers are located at ±30˚, while the rear speakers should be positioned approximately ±110˚. There is speculation that rear loudspeakers at ±150˚ provide “more exciting surround effects”.

(to be continued)

Low Frequency Effects (LFE) Channel
The Frequency Effects channel (LFE) is originally developed to carry extremely low (sub-bass) sound effects such as thunder or explosions on a separate channel. This allows the theatres to control the volume of sound effects to suit the size of their sound system and the acoustic environment of their cinema. However, home system may not have a separate subwoofer that can handle such effects. Therefore, modern surround systems often incorporate a bass management system that allows bass on any channel to be fed only to speakers than can handle low-frequency signals.

Basically a home cinema is composed of the following components:

1. Input Device: Any audio/video source that can include high quality formats such as blu-ray. Others include VHS player or video game systems. Some of the newer models include a home theatre PC that acts as a library for video and music content.
2. Processing Device: Input devices must be processed for complex surround sound output.
3. Audio Output: Normally systems come with two speakers but can have up to 10 speakers and an additional subwoofer.
4. Video Output: A large High Definition display that can be LCD, plasma, video projector, rear-projection television or a traditional CRT television.
5. Atmosphere: High-end home theatres have sound insulation to prevent noise from escaping the room and a specialized wall treatment to balance the sound within the room.

So please change the old feed address to this. And happy St. Patrick day to everyone!

• Every floor model television is set its brightness to maximum. Try and ask the salesperson to reduce the brightness of the television you are comparing.
• Display floors are well-lit. Few living rooms are lit that much. See if you can ask them to reduce the light shedding on the picture.
• Blu-ray. If you have a disc that you are familiar with, see if you can use it instead of the TV signal that is normally shown. Blu-ray provides the best picture a television can display, so it makes for the best reference from which to judge. And if you are used to the look of a particular DVD, use it instead.
• Televisions come with many picture presets such as movie, sports, etc. Try all of them to see which is best.
• It is strongly recommended to protect your television with some sort of surge protection. Do not believe the hype that a better protector will somehow improve video quality, but do choose a model with coaxial inputs and outputs for your cable or antenna.

This concludes the series on television buying guide.

Of course no television can compete with a dedicated audio system. You can consider a home-theatre audio system for maximum impact.

Name: RF (Radio Frequency)
Sources: Antennae, VCRs, cable and satellite boxes
Quality: Lowest, highest for HDTV tuners

Name: Composite Video
Sources: Cable and satellite boxes, VCRs, DVD players, game consoles
Quality: Low

Name: Component Video
Sources: HD cable and satellite boxes, DVD players, HDTV tuners, Blu-ray and HD DVD players, game consoles, other HD sources
Quality: High

Name: RGB
Sources: Computers, video processors
Quality: High

Name: FireWire
Sources: Some HDTV tuners, D-VHS VCRs
Quality: Highest (digital)

Name: DVI-D with HDCP
Sources: Computers; older HD cable and satellite boxes, HDTV tuners and DVD players
Quality: Highest (digital)

Name: HDMI
Quality: HD cable and satellite boxes, DVD players, HDTV tuners, Blu-ray and HD DVD players, game consoles, computers, other HD sources
Quality: Highest (digital)

Black Bars and Unused Screen
The problem with the aspect ratio is that most of the television shows are still broadcasted in 4:3 format. To view them on a wide-screen television without stretching or cropping the picture, you have to waste a portion of the screen by putting bars on either side of the image. Conversely, if you have an old 4:3 television, to watch a wide-screen show you will have to tolerate two bars above and below the picture.

Wide-screen Televisions and 4:3 programmes
If you do not want to waste your wide-screen space on empty bars, listen to a good piece of news. All wide-screen televisions can stretch, crop, or zoom 4:3 programmes to fit the screen. These methods distort the image to some extent, but it is a lot better than having two bars on either side of the screen.