Hi-Rez Redux
Redux
Alert readers will recall that, about a year ago, I wrote a series of pieces on high-resolution audio and its place in the scheme of things. My position was that, particularly for television, it wasn’t particularly important.I took a fair amount of abuse for that position, and got into a fairly lengthy exchange with a top-level post-production guy as well as Bob Dixon of NBC Sports. All this was duly reported in the pages of TV Technology. You remember, right? Sure.
Well, a year has passed. A tumultuous year. And one of the many bits of tumultuosity in my life was the resumption of a life project that has been lurking in the background for twenty years or so – composing music. And that composing, in turn, led to a major upgrade of gear.
So now I am the proud possessor of the latest, hottest Pro Tools workstation, capable of at least moderately hi-rez work (24-bit 48 kHz. audio) and A LOT of tracks. Further, I’ve got some pretty hi-rez plug-ins (including SpectraFoo, which means I can really measure the rez) and a hi-rez reverb (Lexicon 960) all working within the workstation platform. This all talks to the real world through a Yamaha 02R console, which has 20-bit resolution.
More to the point, I’m busy composing some pretty high-tech high-rez electronic music. This is music that uses a lot of tracks (64 plus) for a long time (up to an hour) with a LOT of automation, a fair amount of signal processing, a tremendous amount of surround-sound stuff (all my music is multi-channel with a vengeance), and a huge dynamic range (uh, 96 dB!).
What this means is that I’m really and truly walking the walk these days, not just talking the talk. And so I thought I’d share with you what I’ve noticed, now that I have been dragged kicking and screaming into the 21st Century of hi-rez audio.
Can You Hear A Difference?
The first question, of course, has to be, can I hear a difference with all this increased resolution? And the answer is, interestingly, yes. Well, sort of yes, anyway. CDs passed through the workstation sound distinctly better than CDs converted to analog by the CD player. Sound files imported into the workstation sound really nice on playback.And what do “sound better” and “sound really nice” mean? To me, they mean slightly richer, more luminous, with greater depth and detail than I normally experience.
They also mean “slightly,” suggesting that the difference is in fact pretty small.
And finally, I have to ‘fess up, I’m not sure I could reliably pick out the difference all the time in controlled blind comparison tests. It may “sound really nice,” but is it “enough nicer” that I could pick it out 95% of the time? I’m not at all sure that it is.
More Tales From The Audio Crypt
But there’s more to this. At one point this summer, a colleague (Roger Talkov of DVD Labs) brought in a major label classical surround 24/96 DVD-A he was mastering to check out over my surround monitor system. We used a fairly cheap consumer DVD-A player and just plugged it into my surround monitor path.Surprise! There was a lovely soft “depth” and musical richness to the sound that was both really distinctive and satisfying. Further, we were able to compare a (Grammy-winning) pop 16-bit/44.1 kHz. CD against a 24-bit/96 kHz. DVD-A release of the same album and observe that a similar difference seemed to be present. A softness, a kind of delightfully crunchy musical depth that replaced the “edge” on the recording. Really nice, like I said.
What causes it remains a question. For reasons I’ll get to in a minute, it can’t be the bit depth. My speakers are good to 17 kHz., but roll off steeply above that, so I’m dubious that it is the increased bandwidth. The stock converters in the cheap consumer player can’t be any great shakes. So, it remains a question, a good question.
Meanwhile, the music I’m working on has some serious dynamic range. One piece that I recently finished actually starts at –90 dBFS and slowly rises to –60 dBFS (and then, VERY slowly, crescendos all the way to 0 dBFS – but that’s another story). What’s interesting is that it is usually very hard to hear the –90 dBFS stuff. Hard enough that one early listener called me to wonder why the music didn’t start for the first several minutes. And when I got the stuff mastered for DVD surround, the mastering facility called to ask me where on the tape the piece started – they weren’t sure, even though I had it logged.
Now, -90 dBFS is the 15th bit. Some 9 bits and 54 dB above the 24-bit digital black noise floor of the workstation. And the truth is, we can’t hear even that crass lo-rez bit, under any reasonable playback circumstances, without anything else going on! Interesting, eh?
What Does It All Mean?/A Promo
What’s the point? Well, I personally think that the point is that we don’t understand, yet, what it is that we’re doing with hi-rez. Our hi-rez efforts are, apparently, affecting the quality of sound in ways unrelated to bit depth or bandwidth. We speculate, rant and dither about what “those ways” are, but the truth is that we really don’t know. And, truth be known, it’s pretty subtle, however pleasurable.A second, more important point, to me, is that surround sound is very powerful medicine. Much MORE powerful, MORE pleasurable, MORE meaningful than hi-rez. And, yes, we can instantly hear the difference that it makes. No question at all.
My final point is that you can, if you wish, check this all out for yourselves.
Four of my pieces are on display through February 10th, 2002 as “virtual sound sculptures” at the Chapel Gallery in Newton, MA. If you’re in the area, stop in and check them out – no charge. Six-channel surround sound compositions (I use an overhead channel in addition to a standard 5.0 array). Various listeners have told me that these pieces are really very beautiful. I’d love for any of you who can to have a listen, tell me what you think. For info on the exhibition, contact Sean MacLean and/or http://www.bostonsculptors.com. [see also here for photos and here for a piece on the playback issues of the event - WebEd. 2009]
Next month we’ll talk about an audio guy’s take on video rez. Uh-oh!
Thanks for listening.
