JVC SV-D723GD DVD-Audio/Progressive Player
March 2001By Mike McGann
It's been more than two years since I sat in a hotel suite in Osaka, Japan, and heard DVD-Audio for the first time. While the demo, put on by Panasonic parent Matsushita, was impressive, those of us in the room had a sense that it was a bit cooked. A quick look at a colleague's sound pressure meter confirmed that the DVD-Audio samples had been played at about 3 dB louder, which can make it seem better in a quick demo. As usual, I decided to reserve judgement on DVD-Audio until I got my hands on a player, which I was assured would only be weeks, or certainly just a couple of months, away.
Time passed. Rival Super Audio CD shipped to rave reviews, including my own. We learned the horrible truth about pregnant chads. After about 100 weeks, finally a pair of DVD-Audio players showed up in my lab, JVC's single-disc XV-D723GD and Kenwood's five-disc DV-4070-B within a day of each other.
While there is some passing comparison between the two, the functionality of the units is somewhat different, as the Kenwood doesn't have progressive video output and seems more targeted to the music aficionado. I address the Kenwood in detail on page 70 in this issue.
JVC, though, seems to have aimed for a home run right out of the box, offering a DVD player to cope with virtually any media, outputting high-resolution audio and video.
For those of you unclear about this whole DVD-Audio thing, here's a quick primer: CDs are encoded at 16 bits and sampled at 44.1 kHz. For you non-tech-heads, that means CDs use moderate compression and only record sound up to about twice what humans can hear. DVDs generally use 24 bit, 48 kHz.
DVD-Audio uses 24 bit/96 kHz. You might argue that you can't hear anything above 18,000 Hz, but two issues come into play: psychoacoustics and the comb filter effect.
Psychoacoustics involves how your brain perceives sound and how it interacts with the room you're in. You might not be able to hear high frequencies, but they cause other things in your room and (gasp!) your body to vibrate in harmony, called secondary harmonics by some. Those slightly audible sounds impact how you perceive sound. The more fully sampled the frequency range, the more of these secondary harmonics are reproduced.
