Conversation: The Sound Of High Definition
Dear Gary:
I hope you have survived the weather this past winter season!
With the Winter Games, the Academy Awards®, and the Grammys® all produced in high-definition and Dolby Digital® 5.1 surround sound behind us, everyone’s attention is focused on the pending launch of HD DVD and Blu-ray Disc formats.
The first HD DVD players and software are now on sale. Without a doubt, the availability of an HD playback device––and therefore more HD content––will be a real boom for early adopters who have invested in an HD display and yearn for more and more content to play on it. Of course, we believe that high-definition entertainment is “more than just a pretty picture.” We’re looking forward to experiencing the more immersive sound available through these new formats.
Two next-generation audio codecs from Dolby—Dolby Digital•Plus and Dolby TrueHD—are included in the first High-Definition DVD players from Toshiba, the HD-XA1 and HD-A1.
Dolby Digital•Plus technology, as employed in next-generation optical media, offers greater fidelity, more surround sound channels, and less compression than available on DVD. The result is a listening experience characterized by warm, deep bass performance and detailed high-frequency response. We refer to it as “Picture Perfect Sound.” Dolby Digital•Plus provides an enhanced listening experience that complements the high-definition picture quality and value-added features included on next-generation software.
Dolby TrueHD technology delivers true high-definition sound, with lossless audio quality that is bit for bit identical to that of a studio master recording. Dolby TrueHD can support up to eight full-range channels of lossless surround sound on the HD DVD format, and sample rates of up to 192 kHz.
As with all new formats, there comes the inevitable confusion over connection and compatible playback. Besides offering new audio technologies, next-generation players may also be equipped with the capability to simultaneously mix and send out as many as three different audio sources. For this reason––and others––most first-generation HD DVD and Blu-ray Disc players will include decoding inside the player.
To assist your readers’ understanding the implications of these new feature sets and how to connect them to their AVR to achieve the best performance possible, Dolby has created two white papers: “Ensuring Compatibility Between Next-Generation High-Definition Disc Players And Your A/V System” and a “Dolby Audio Coding For Future Entertainment Formats.” You can access both at http://www.dolby.com/consumer/technology/trueHD/AVRs/
trueHD_avrs_1.html and http://www.dolby.com/assets/pdf/tech_library/ DPlus_TrueHD_whitepaper.pdf, respectively.
Recently manufactured AVRs or processors equipped with HDMI version 1.1 or external analog audio inputs can experience the full performance capabilities of Dolby Digital•Plus and Dolby TrueHD when these signals are decoded inside the player.
As you can imagine, connecting HD players to the more than 40 million AVRs and processors equipped with Digital Audio Outputs is also important. To insure compatible playback, Dolby introduced a new real-time encoder, which will be referred to as Dolby Digital Compatible Output in training, marketing, and sales resources. Dolby Digital Compatible Output re-encodes the mixed signal in the high-definition player as real time at 640 kbps Dolby Digital bit stream. Next-generation optical players equipped with Dolby Digital Compatible Output can connect to legacy audio-visual receivers and deliver a higher quality 5.1 channel listening experience when compared to conventional DVD audio.
Craig Eggers, Senior. Manager, Consumer Electronics Technology Marketing, Dolby Laboratories
Editor-In-Chief and Publisher Gary Reber Comments:
Thank you, Craig, for this contribution and for your participation as a presenter on the 2006 Home Theater Cruise.
You can E-mail Widescreen Review @ mailto:editorgary@widescreenreview.com