February, 2001 | Readers of this column know that
I'm a fan of DVD-Audio. As a musician, audio engineer, and
consumer of recorded music, I'm tremendously excited by
the potential of this new DVD format and anticipate that
its benefits will transform the way that we experience our
favorite bands or artists. But of the few DVD-Audio products
that have been released, only a select few demonstrate the
real advantages of this new "meta" format. In order for
DVD-Audio to become the successor to the aging compact disc
format and find a place of favor, there must be a substantial
improvement in the quality of the experience. The DVD-Audio
titles that have been made available so far fail to reach
the necessary standard. It comes down to a matter of recording
resolution and mixing philosophy.
The fidelity of CDs is based on the particular technology
of their digitization scheme and the specific parameters
associated with that technology. Compact discs use pulse
code modulation (PCM) to convert analog signals into the
bits and bytes pressed into the surface of an optical disc.
The familiar 44.1kHz/16-bit Red Book standard defines the
maximum "theoretical" quality level of any music recorded
according to those standards. Most CDs come up somewhat
short of this ideal, but are still markedly better than
the average analog LP. DVD-Audio brings a new set of parameters
to PCM encoding methodology. Instead of digitizing at 44.1kHz/16-bit,
the new machines are capable of playing back at substantially
higher rates and with word sizes that extend all the way
to 24 bits (although the limitations of the conversion hardware
makes achieving that standard virtually impossible).
High-resolution audio is anything recorded at 96kHz/24-bit
or higher. However, almost all of the DVD-Audio titles available
now or on the way have not been recorded at 96kHz/ 24-bit,
but merely transferred at some point in post-production
using a high-resolution converter. Contrary to the prominent
stickers and lettering on DVD-Audio packaging and the pronouncements
by industry "authorities" about how the sound quality is
astonishingly clear and beyond anything you've ever heard,
the releases so far are predominantly 5.1 remixes of analog
master tapes or low-resolution digital masters. How can
you hope to attract audiophiles and the music-consuming
public to the new format, when the software being made available
doesn't even take advantage of one of its major selling
points? It's simply another case of LoRez in equals LoRez
out. The fidelity of any recording is established at the
time of the original session and cannot be magically transformed
via HiRez digital copying later on. Yet this has been hailed
as a quality improvement as profound as "moving from B&W;
television to color." A better analogy would be the "colorization"
of classic B&W; films...a development that didn't exactly
warm the hearts of the creative community.
There are practical and technical reasons why 96kHz/ 24-bit
"source" recordings are not the centerpiece of the new DVD-Audio
format. It's expensive and complicated to produce new recordings
using only high-resolution equipment. AIX Records has produced
and released over 10 new high-resolution recordings. We've
recorded jazz ensembles, classical music by orchestras and
chamber groups, and a variety of acoustic ensembles including
bluegrass bands, solo acoustic guitar, and percussion. It
makes a tremendous difference. The music occupies the space
with the listener instead of existing behind the speakers.
We produced a DVD-Audio sampler disc (available at http://www.aixrecords.com),
which demonstrates the fidelity of high-resolution audio
and the reality of "immersive" 5.1 channel surround mixing.
It's a "Tribrid" disc that's playable on DVD-Audio, Video,
and ROM devices.
Where the current range of DVD-Audio products do take
advantage of the new spec is in the area of 5.1-channel
surround sound. The Fleetwood Mac Rumours DVD-Audio title
can never be high-resolution (it was recorded on 24-track
analog equipment), but it is a wonderful example of what
can be done with multichannel mixing. The listener is surrounded
by musical parts and vocal harmonies. The same music that
you've been listening to for all these years is reborn and
sounds fresh again. There are things in the music that can
be heard for the first time because they exist in their
own "sonic space." Mixing a surround project is actually
easier than trying to mix the same project in just two speakers.
There's so much more room to place the individual tracks.
Engineers are experimenting with this newfound sense of
freedom and no one is really sure how to approach the world
of 5.1-channel surround.
Maybe there are several valid ways to mix a multichannel
project. Some consumers will enjoy being placed in the middle
of the musicchoosing the so-called "stage" mixwhile
others will prefer to retreat to the familiarity of the
best seat in the house, the "audience" mix. During the mixing
of the Brahms Piano Quintet in F Minor, I was heartened
to find that the musicians enthusiastically endorsed the
aggressive placement of the instruments around the room.
The listener hears the individual parts from the middle
of the ensemble and can adjust his or her own blend by moving
closer to the instruments that need to be louder. Admittedly,
the experience is completely unlike attending a concert,
but it is nonetheless compelling and engaging. So there's
good news and not-so-good news about how the DVD-Audio format
is being handled. There is a revolution coming... you just
can't quite hear it yet.