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[1.12] What about music on DVD: DVD-Audio
and SACD?
When DVD was released in 1996 there was no DVD-Audio format,
although the audio capabilities of DVD-Video far surpassed CD. The
DVD Forum sought additional input from the music industry before
defining the DVD-Audio format. A draft standard was released by
the DVD Forum's Working Group 4 (WG4) in January 1998, and version
0.9 was released in July. The final DVD-Audio 1.0 specification
(minus copy protection) was approved in February 1999 and released
in March, but products were delayed in part by the slow process
of selecting copy protection features (encryption and watermarking),
with complications introduced by the Secure Digital Music Initiative
(SDMI). The scheduled October 1999 release was further delayed until
mid 2000, ostensibly because of concerns caused by the CSS crack
(see 4.8), but also because the hardware wasn't quite ready, production
tools weren't up to snuff, and there was lackluster support from
music labels. Pioneer released the first DVD-Audio players (without
copy protection support) in Japan in late 1999.
Matsushita released Panasonic and Technics brand
universal DVD-Audio/DVD-Video players in July 2000 for $700 to $1,200.
Pioneer, JVC, Yamaha, and others released DVD-Audio players in fall
2000 and early 2001. By the end of 2000 there were about 50 DVD-Audio
titles available. By the end of 2001 there were just under 200 DVD-Audio
titles available.
DVD-Audio is a separate format from DVD-Video.
DVD-Audio discs can be designed to work in DVD-Video players, but
it's possible to make a DVD-Audio disc that won't play at all in
a DVD-Video player, since the DVD-Audio specification includes new
formats and features, with content stored in a separate "DVD-Audio
zone" on the disc (the AUDIO_TS directory) that DVD-Video players
never look at. New DVD-Audio players are needed, or new "universal
players" that can play both DVD-Video and DVD-Audio discs. Universal
players are also called VCAPs (video-capable audio players).
A plea to producers:
Universal players are rare, but you can make universal discs
easily. With a small amount of effort, all DVD-Audio discs can be
made to work on all DVD players by including a Dolby Digital version
of the audio in the DVD-Video zone.
A plea to DVD-Audio authoring
system developers: Make your software
do this by default or strongly recommend this option during authoring.
DVD-Audio players (and universal players) work
with existing receivers. They output PCM and Dolby Digital, and
some will support the optional DTS and DSD formats. However, most
current receivers can't decode high-definition, multichannel PCM
audio (see 3.6.1 for details), and even if they could it can't be carried
on standard digital audio connections. DVD-Audio players with high-end
digital-to-analog converters (DACs) can only be hooked up to receivers
with 2-channel or 6-channel analog inputs, but some quality is lost
if the receiver converts back to digital for processing. New receivers
with improved digital connections such as IEEE 1394 (FireWire) are
needed to use the full digital resolution of DVD-Audio.
DVD audio is copyright protected by an embedded
signaling or digital watermark feature. This uses signal
processing technology to apply a digital signature and optional
encryption keys to the audio in the form of supposedly inaudible
noise so that new equipment will recognize copied audio and refuse
to play it. Proposals from Aris, Blue Spike, Cognicity, IBM, and
Solana were evaluated by major music companies in conjunction with
the 4C Entity, comprising IBM, Intel, Matsushita, and Toshiba. Aris
and Solana merged to form a new company called Verance, whose Galaxy
technology was chosen for DVD-Audio in August 1999. (In November
1999, Verance watermarking was also selected for SDMI.) Verance
and 4C claimed that tests on the Verance watermarking method showed
it was inaudible, but golden-eared listeners in later tests were
able to detect the watermarking noise.
Sony and Philips have developed a competing Super
Audio CD format that uses DVD discs. (See 3.6.1
for details.) Sony released version 0.9 of the SACD spec in April
1998, the final version appeared in April (?) 1999. SACD technology
is available to existing Sony/Philips CD licensees at no additional
cost. Most initial SACD releases have been mixed in stereo,
not multichannel. SACD was originally supposed to provide "legacy"
discs with two layers, one that plays in existing CD players, plus
a high-density layer for DVD-Audio players, but technical difficulties
kept dual-format discs from being produced until the end of 2000,
and only then in small quantities. Pioneer, which released the first
DVD-Audio players in Japan at the end of 1999, included SACD support
in their DVD-Audio players. If other manufacturers follow suit,
the entire SACD vs. DVD-Audio standards debate could be moot, since
DVD-Audio players would play both types of discs.
Sony released an SACD player in Japan in May 1999
at the tear-inducing price of $5,000. The player was released in
limited quantities in the U.S. at the end of 1999. Philips released
a $7,500 player in May 2000. Sony shipped a $750 SACD player in
Japan in mid 2000. About 40 SACD titles were available at the end
of 1999, from studios such as DMP, Mobile Fidelity Labs, Pioneer,
Sony, and Telarc. Over 500 SACD titles were available by the end
of 2001.
A drawback related to DVD-Audio and SACD players
is that most audio receivers with 6 channels of analog input aren't
able to do bass management. Receivers with Dolby Digital and DTS
decoders handle bass management internally, but 6-channel analog
inputs are usually passed straight through to the amplifier. Without
full bass management on 6-channel analog inputs, any audio setup
that doesn't have full-range speakers for all 5 surround channels
will not properly reproduce all the bass frequencies.
If you are interested in making the most of a DVD-Audio
or SACD player, you need a receiver with 6-channel analog audio
inputs. You also need 5 full-frequency speakers (that is, each speaker
should be able to handle subwoofer frequencies) and a subwoofer,
unless you have a receiver that can perform bass management on the
analog inputs, or you have an outboard bass management box such
as from Outlaw Audio.
For more on DVD-Audio, including lists of titles
and player models, visit Digital Audio Guide.
[1.12.1] What's the difference
between DVD-Audio discs and DVD-Music discs?
DVD-Music isn't actually an official DVD format, but it has become
a commonly used name for a DVD-Video disc that contains primarily
music. A DVD-Music disc plays in any standard DVD player with video
or still pictures that accompany the audio. As explained in 1.12,
a DVD-Audio disc contains special high-fidelity audio tracks that
can only be played in DVD-Audio players.
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