NEW DELHI: With the craze for high definition TV sets with crystal clear digitised images being reflected in the new product launches and sales promos of companies, people are missing out on the advancement of HD sound and that, unfortunately, does not come automatically with HD TVs.

In fact, most are even unaware that in the rush to compress a thousand songs in a portable player, the MP 3 format gives us sound that is 90 per cent less perfect than the originals, and some companies are working to undo that and restore MP 3 to what they call "sound of the 70s", clear, rich and original.

High Definition TV will be one of the great success stories of 2007, according to a BBC report.

For most, the attraction is a bigger telly with a better picture - but what about the sound? What is HD sound anyway? And do we need anything more than our shiny new TV to get it? BBC‘s Dan Simmons ‘looked into‘ the sound, literally.

Dolby and DTS are passé now, and next generation of Dolby and DTS - Dolby True HD and DTS-HD (or Master DH Audio to give it its full name) are making their impacts felt.

Clare Newsome of www.whathifi.com says: "We‘ve got the next generation of Dolby and DTS - Dolby True HD and DTS-HD (or Master DH Audio to give it its full name). From the names ‘master‘ and ‘true‘ you‘re being told that it‘s uncompressed.

"You watch something like ‘Casino Royale‘ and it‘s just amazing, a whole extra level of cinematic. And the chances are that will sound better than you‘ve heard in a small multiplex."

Newsome says: "There is no standard for HD sound. A lot of people are staring to put it on products and there‘s a lot of potential for confusion out there."

Whilst it‘s important to understand that manufacturers could slap the label HD on any half decent audio system the lack of a standard hasn‘t meant a lack of progress.

But now everything‘s just got one step better. Unlike standard broadcasts most HDTV automatically includes surround sound, and there are now brand new sound formats for HD-DVD and Blu-Ray discs which, for the first time, have the space to carry uncompressed sound.

This delivers a perfect replica of the movie‘s soundtrack through the players‘ HDMI socket.

The HDMI cable typically would run from the player to the amp, which takes the audio and passes on the picture via another HDMI cable to the TV.

The amp decodes the sound signals and sends them to the surround sound speakers. The sound can also be channelled through 6 analogue phono outputs, but this is a more messy solution as far as cables are concerned.

"Trouble is we don‘t yet have all the kit we need to experience it!" Simmons says.

Newsome assures, however, that from this summer there‘s a lot of new kit coming out, a lot of it quite affordable, and a lot of it will include these new HD formats.

Experts says that don‘t rely on your TV speakers - HDTVs may offer the best in vision but the built-in speakers deliver a fraction of what‘s on offer because all HD broadcasts are now in surround sound by default.

Even fancy wireless speakers are not trustable. Some won‘t cope with the new sound formats, so check first. In this case you‘ll need to select a compressed sound format like standard DTS.

BBC quotes Geraldine De Bonus, www.creative.com as saying: "With the change from CD Discmans to MP3 people haven‘t realised but they‘ve lost a huge amount of audio quality. By ripping a CD track to MP3 or WMA a lot of audio is lost."

Unless you‘ve been ripping or copying your CDs in a lossless format chances are you‘ve crushed the amount of data a CD would have given you by 90 per cent - just to get in onto a portable player.

Lossless compression is where a file is reduced in size, but where the algorithm used to do so also allows the exact original data to be reconstructed from the compressed file. More: Lossless data compression

Creative has been improving audio with its soundcards for more than 20 years - mainly aimed at gamers. But as we begin to store more of our media on hard drives it‘s created kit that tries to upgrade our low-grade MP3s to how they should sound.

Darragh O‘Toole of Creative explains: "If you‘re looking at the ‘before‘ and ‘after‘ sound (shown in EM graphs) waves you can see that in the MP3 version all of the changes in audio energy levels are actually dumbed down, curtailed. So we understand what has happened during the process.

"If you look at the ‘after‘ phase [of our new system] you can see how we‘ve restored these. So the strength and energy has been restored to things like the bass drums, you‘ll hear it come much more alive with crisp snare drums and nice, tight high hats at the high end."

In March, SRS Labs, (NASDAQ:SRSL), a leading supplier of audio, voice and surround sound technology solutions, announced the availability of new SRS WOW HD(TM) and SRS Mobile HD(TM) audio drivers for Windows Mobile 6.

Windows Mobile device manufacturers may license these audio solutions to enable a 5.1 surround headphone listening experience for mobile TV and video applications.

Further, device manufacturers and mobile operators can rest assured knowing that these audio technologies have achieved "Designed for Windows Mobile" certification through the Windows Mobile 2 Market certification and marketing program.

Designed for mobile broadcast services like Digital Video Broadcast - Handheld ("DVB-H") and for digital video downloads, the SRS Headphone 360(TM) technology in SRS Mobile HD is a full audio rendering solution that enables handset makers and mobile operators the ability to deliver an immersive surround sound headphone experience with low battery impact for the exploding Mobile TV and mobile video market.

With SRS Mobile HD, Windows Mobile users can experience "personal" 5.1 home-theatre surround on the go, through their own favourite headphones or earbuds the SRS software on the handset does the processing.

"With the release of Windows Mobile 6 comes a new wave of functionality for business professionals and consumers alike," said Mike Canevaro, senior director of business development, SRS Labs.

Each of the audio drivers is easy-to-implement and sit within the audio path. They enhance any audio going through the ARM-based multimedia applications processors such as Texas Instruments‘ OMAP devices and Marvell‘s PXA-27x (formerly Intel Xscale) processors. Additionally, SRS Labs delivers a full consumer graphical user interface that can be customized by the handset maker.

All these changes mean our digital sound is likely to stage a very unsung, overlooked, and quiet revolution.