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Meridian - Everywhere! Meridian's MLP lies at the heart of every DVD-A player, every disk (5/1/2004)

Meridian Audio Limited (Booth #17220, Las Vegas Convention Center, South Hall 1 & 2), is known internationally for its acclaimed hi-fi and home theater products, where it is the recognized leader in all-digital audio/video systems with such products as the multiple award-winning Reference Series 800 player and 861 surround processor, the acclaimed DSP7000, DSP8000 and other DSP-based loudspeaker systems, and the extensive, elegant new G Series.

What is perhaps less well known is the widespread nature of Meridian's innovative technology. For many years, Meridian has written its own software for surround decoding, optical disc navigation and system control, rather than buying it in from elsewhere, allowing the company to react quickly to new developments and solve problems caused, for example, by an errant disc. However, the company was also responsible for one of the core technologies in the latest and most advanced audio distribution format, DVD-Audio, thanks to MLP - Meridian Lossless Packing - the lossless compression technology employed in every DVD-Audio disc.

DVD-Audio is a member of the DVD (Digital Versatile Disk) family, the most successful consumer format ever. DVD-Audio uses the same DVD disk technology, with the ability to store 4.7 GB per layer, per side, and each side can have up to two layers. But instead of storing video on the disk, the majority of the space is used to store super-quality multichannel advanced resolution audio - six channels of up to 96 kHz, 24-bit sampling or stereo at up to 192 kHz. That means a frequency response of up to 100 kHz and a dynamic range in excess of 140 dB over that entire range - a level of quality and detail unmatched by any other audio format.

But there was a challenge in getting this super-quality audio on to the disc. The data rate of DVD-Audio is 96 Megabits per second. This would limit the playing time of 5-channel audio at 96 kHz sampling to 65 minutes and 20-bit resolution, while 6 channels of 24/96 would exceed the allowable data rate. The obvious answer was compression, which is how a movie can fit on to a disk, but lossy compression had been ruled out by the record industry in specifying DVD-Audio. So lossless compression - where the data recovered from the disk is identical to that originally encoded on it - was the way to go. An international competition was held to choose the technology, and Meridian's MLP was the clear winner.

MLP allows 6 channels of 24/96 super-quality PCM audio to be carried on the disc, with a playing time of up to 86 minutes - or 74 minutes while leaving room for popular extras such as music videos, lyric sheets, slide shows, DVD-Video player compatibility and all the other features that make DVD-Audio the outstanding advanced-resolution music carrier and market leader it is today.

In a DVD-Audio player, MLP decoding is intricately woven into the high resolution PCM audio technology used for DVD, making the decode process relatively inexpensive - the cleverness is in the encoding system used during authoring, requiring much less sophisticated processing in the player itself. In addition, MLP is extensible, with metadata and flags in the data stream that can signal the player and provide information about the type of material being played. For example, in addition to supporting conventional 5.1 surround, MLP can allow DVD-Audio - or future media using MLP technology - to support different channel configurations and surround-sound techniques, including those that have not yet been defined.

Today, MLP is included in the over 160 DVD-Audio player models, from 35 manufacturers - a total of more than 10 million players - plus the two million or so computer-based DVD-A replay systems now in the marketplace, and licensing of the technology is handled by Dolby Laboratories (booth #17214, adjacent to Meridian's booth). Every time you see the MLP logo on any DVD-Audio player, or on any DVD-Audio disk, you're seeing - and hearing - Meridian technology in action. Meridian - at the heart of DVD-Audio.

www.meridian-audio.com