to High Definition Audio!
by Jim Bray
Now that DVD video
is turning the home theatre market on its ear, "high definition"
audio is poised to up the ante for music lovers as well.
more than one format promising superior sound - leading to the possibility
of another standards war that's destructive to everyone (especially consumers!).
Proponents of "HD-Audio"
are so high on the formats that they're practically promising the sound
will make today's compact discs sound like AM radio. I've heard one of
the formats, and it sounded very good, indeed. Unfortunately, it was at
a trade show and I don't trust anything I see or hear at a trade show
- everything looks and sounds good.
Then again, I didn't
trust DVD Video when I first saw it at a show a few years back - but since
then have jumped so firmly upon that bandwagon that I left footprints
There are two major
competitors for the ears of consumers, one of which is supposed to be
compatible with today's compact disc players. The compatible system is
Sony and Philips' Super Audio CD, a hybrid disc that contains the normal
reflective data layer of a CD player, enhanced with a second, high density
"semi-reflective" layer. This second tier offers the "ultra
high quality" stereo sound as well as multi-channel, text and graphics
Philips says the
"SACD" is consumer friendly because of its forward and backward
compatibility. Naturally, this is only partly true: you may indeed be
able to play the disc in today's CD player, but to get all the extras
you need a new player - and an audio system capable of handling the enhancements.
The other standard,
DVD Audio, is incompatible with today's CD and DVD players, though some
new players hitting the market later this year will handle DVD Audio along
with DVD Video.
DVD's high storage
capacity allows for much higher sampling rates or much longer playing
times than compact discs. Demos I saw at the trade showpromised
"only" 74 minutes of playing time (the same as an audio compact
disc), but with a 24 bit "sampling rate" of up to 96 kHz (this
"technobabble" means the number and size of the "digital
pictures of the music" the recording device takes each second), which
is more than twice a CD's.
You can also add six
channel surround sound to the mix.
one of DVD Audio's chief cheerleaders, says the format allows the reproduction
of overtones up to 100 kHz (the human hearing threshold is about 20 kHz
- so your dog will be happy, too!), which leads to a more pure and realistic
sound. They say this immerses you in a veritable sonic sea and, as one
who loved quadraphonic sound when it limped onto the market in the 1970's,
I think that's good.
Remember, when you
listen to a live show you're not only hearing the music played in front
of you (or wherever it is), you hear it reflected from walls, trees, or
whatever else happens to be around as well. So this "immersive"
experience can not only give a more realistic feel to the music - something
that audio manufacturers have been trying to duplicate digitally with
"concert hall-type" settings on their receiver/processors -
it also offers the opportunity for some really wild, studio-created effects
- like music swirling around you from speaker to speaker.
These sound like neato
formats for high end audiophiles, and that's fine. To be honest, however,
I'm not sure they'll be a real mainstream item. As good as the demos have
sounded, I'm not sure I care as much for the inaudible frequencies (after
all, they slice them off in the minidisc format - to cram the audible
parts onto the little disc - and minidiscs still sound terrific) as I
do for compatibility and the extended playing time you can get from a
But I'm willing to
be convinced otherwise
Tell us at TechnoFile what YOU think