When most people think of DVD, what they have in mind is DVD-Video, the fastest-starting consumer-entertainment format in history. As you'd expect, the DVD format was defined from the start with an emphasis on video presentation.
Of course musicians know that the “other” DVD format is DVD-Audio (DVD-A), which uses the same physical medium as DVD-Video. DVD-A has different content definitions that emphasize audio fidelity and offers navigation features designed to appeal to the music listener. For music producers, it might seem natural that DVD-Audio would be the format of choice. Alas, the situation is not that simple.
DVD-Video has had a mature specification for several years and has an installed base of many millions, but the specification for DVD-Audio was only truly finalized in 2001. Today, “combi” players for both DVD-Video and DVD-Audio discs are available, but they represent a small fraction of players in the field, and sales of DVD-Audio titles have languished.
DARE TO COMPARE
What's so great about DVD-Audio? The table “DVD-Video Versus DVD-Audio” compares the features of DVD-A and DVD-Video. Both can deliver uncompressed 24-bit PCM stereo at sampling rates well beyond those of CD, although DVD-Audio is capable of sampling rates as high as 192 kHz, while DVD-Video tops out at a “mere” 96 kHz.
When it comes to surround, though, DVD-Audio wins the fidelity contest hands down. In DVD-Video, all multichannel audio data is compressed, using either Dolby AC-3 or DTS. Depending on the format and data rate selected, audio fidelity will be affected to a greater or lesser degree. In DVD-Audio, on the other hand, up to six full-bandwidth channels can be rendered, without compression, at resolutions as high as 24 bits and sampling rates as high as 192 kHz (stereo).
Though DVD-Audio does not use data compression as such, it does make use of lossless bit-packing to deliver multiple channels at higher resolutions and sampling rates and to extend playing time. The bit-packing technique, Meridian Lossless Packing (MLP), guarantees bit-for-bit accuracy of audio data, eliminating any potential loss of fidelity.
In DVD-Video, still pictures are always tied to sound, so that it becomes impossible for the viewer to switch to a different still picture without also jumping the audio to a new location. In DVD-Audio, the listener can surf liner notes, artist pictures, or lyric sheets freely while audio continues uninterrupted.
DVD-Video also includes options for user interactivity, driven by small sequences of commands that are embedded in the navigational structure of the disc. Commands available include conditional logic, random-number generation, and full Boolean and hexadecimal arithmetic, so that user interaction can be fairly rich. In DVD-Audio, such options are severely limited.
GET ON BOARD
Although the number of DVD-Audio players in the field is tiny in comparison to that of DVD-Video, there are good reasons for musicians to use the DVD-Audio format. Though DVD-Audio releases for the mass market have not been successful so far, the medium has a following among serious audiophiles. If you're interested in targeting that market, then DVD-Audio may be a viable option for you. Also, although the current penetration is small, it's growing, and record labels and manufacturers are lining up to push the format more strongly into the market.
Maybe the best reason for musicians to look at DVD-Audio today is the opportunity it provides for multichannel and high-resolution production. A DVD-Audio/Video combi player is the only device you can buy in a standard consumer-electronics store that will play stereo audio at 192 kHz and play multichannel surround audio without data compression. With low-cost DVD-R burners and media and the advent of reasonably priced DVD-Audio authoring packages, DVD-A becomes an excellent way for professionals to exchange uncompromised reference discs during production and promotion.
DVD-A PRODUCTION TOOLS
Because of DVD-Audio's limited popularity, far fewer tools are available for production, and the tools are generally more expensive than the equivalents for DVD-Video. Until recently, in fact, any DVD-Audio capability involved an investment well into five figures.
Fortunately, that is changing. Vendors of professional DVD-A solutions, such as Sonic Solutions, have introduced significantly less expensive versions of their systems, and new entrant Minnetonka Audio Software offers DVD-Audio tools that are affordable to a wide range of production professionals.
For several years, Sonic Solutions was the only company that offered tools for DVD-Audio production. Facing a narrow market, their DVD-Audio Creator package was priced high and tied to the company's high-end audio workstations, for a total system price in the tens of thousands. More recently, Sonic has reduced the price of DVD-Audio Creator and has introduced a lite version, DVD-Audio Creator LE, which incorporates technology licensed from Matsushita. This Windows 2000 program is capable of standalone operation and can be combined with Sonic's higher-end DVD-authoring tools for the creation of DVD-Audio/Video hybrid discs that are compatible with any DVD player. DVD-Audio Creator LE supports most of the provisions of the DVD-Audio spec and includes capability for CPPM copy protection.
Minnetonka offers two versions of its discWelder DVD-Audio authoring software, which runs under Windows 98, 2000, NT, or XP (see Fig. A). DiscWelder Steel ($495) provides bare-bones DVD-Audio capability, suitable for creating DVD-Audio reference discs with high-resolution stereo or multichannel PCM. The program is a snap to use and is certainly the easiest and fastest way to produce a basic DVD-Audio disc. DiscWelder Chrome ($2,495) is a substantially enhanced version that supports multistill slide shows with transition effects, navigation from multiple menus, and DVD-Audio/Video hybrid-disc formatting. Chrome also accepts high-resolution/high-sampling rate surround as MLP-packed audio files. The company offers its MLP encoder SurCode MLP under license for $2,495 or bundled with Chrome for $4,490.
Reviewing a DVD-Audio title during its production has always been an issue. Creative Labs has announced that the top-end version of its Sound Blaster line, Audigy 2 (starting at $129), will support DVD-Audio. However, it seems the playback of DVD-Audio data sets will not be possible from a hard drive — you'll have to play them back from a DVD disc, somewhat limiting the value of Audigy's DVD-Audio capability for production. Fortunately, the low cost of DVD-R burners and media make it easy to do a quality-assurance review from a burned disc in a player.
DVD-Video Versus DVD-Audio
Both DVD-Video and DVD-Audio are capable of rendering stereo audio with higher fidelity than CD. For multichannel surround, DVD-Video requires data compression (Dolby AC-3 or DTS), but DVD-Audio can render up to six channels of uncompressed audio at high resolutions and sampling rates.
Stereo Audio Optionsdata-compressed stereo (Dolby AC-3, DTS, MPEG-2); uncompressed PCM at 16-, 20-, or 24-bit resolution; sampling rates of 48 or 96 kHzuncompressed PCM at 16-, 20-, or 24-bit resolution; sampling rates from 44.1 (CD standard) to 192 kHzMultichannel Surround Options5.1 discrete surround using Dolby AC-3 or DTS data compression6-channel surround, uncompressed, at resolutions as high as 24 bits and sampling rate of 96 kHzVisual Presentationfull-motion video or still pictures (fixed presentation)still pictures only, with user navigation independent of audio; video may be added by creating DVD-V/DVD-A hybrid discsInteractivityextensive user interaction possiblelimited user interaction possible