Positive Feedback ISSUE 4
december/january 2003

Max is Back!! Whither Multi-Channel?
by Max Dudious

My task in the coming months is to keep the PosFeed community up to date on things multi-channel; industry news, new equipment, and new CD releases. I’ll also try to keep you up to date on John Ashcroft’s crackdown on "some dudes." This assignment assumes you are interested in multi-channel’s development as a technology for music-only, and as a nice adjunct to your big-screen TV. Some of you have never thought much about it, and for those of you quester-dudes who seek the grail of perfect sound and have really killer systems 2 die 4, why should you? But for the rest of us, why bother with multi-channel? I’ll try to answer that question in the succeeding pages.

In my solo sailing around the uncharted and treacherous waters of the audio press, I have found that nothing stirs the mind of the true audiophile more than challenging accepted shibboleths, like, "Why bother with multi-channel? Stick with stereo!" We have "worked out" the problems of stereo to a greater extent than ever before. We have a handle on problems that computer- assisted-design and computer-assisted-manufacture (our old friends CAD and CAM) have worked out for us, such as loudspeaker box resonance and diffraction, even raw driver resonances; we have better-than-ever software systems (CDs, SACDs, DVD-A CDs) for data (music) storage and playback; we know more about controlling room resonances and nodal points with special computer packages and room treatment materials; we’ve even finally figured out why speaker cables sound differently. We can, the argument goes, get more out of a conventional stereo rig in its room than ever before. Why bother with the gimmicks and audio trickery of multi-channel?

To which I’d answer, the old paradigms for gimmicks and audio trickery give the technology a bum rap. It all began with attempts at multi-channel LPs back in the days when I thought having a locomotive chug through my dorm room’s listening space was, well... cool. Cool was having different instruments in Bartok’s Concerto For Orchestra, Pierre Boulez, N.Y. Philharmonic (Columbia M32132�well actually the quadraphonic version) come flying at me from all directions, with the randomness of a B-17 under flack attack in one of those 3-D movies, until I got tired of having to duck and twist in my chair. Sure, it’s cool if you’re thirty and that’s still your idea of multi-channel: steam engines and flying woodwinds. But really, who needs that?

Yet, the same factors that went into making stereo a more lifelike facsimile of acoustic instruments in an acoustic environment also help to make multi-channel a more convincing reproduction of that facsimile we’re all after. I won’t get into which is a better format, SACD or DVD-A, because I’m not an engineer, and there are the usual tradeoffs associated with each. I will say the expected "war" between these data handling methods everyone expected two years ago never developed, and with the growing numbers of new releases in SACD and SACD multi-channel (SACD-M) by the various labels, it seems it never will.

So what’s the big deal? Whither, to what situation, one might ask, to what end can multi-channel for music take us? I think it can take us to an incremental, asymptotic, (ever approaching but never perfectly achieving) facsimile of live acoustic instruments in the acoustic venue where it was recorded. One might ask, how can multi-channel improve on stereo? To which I’d answer, "If properly engineered at the recording level, and at the playback level, multi-channel can get closer to the illusion of live musicians in your listening space than stereo, all things being equal."

Who first said, "The most important component in your stereo system is your room."? I can’t remember the guy’s name (Leo Beranek?), but I agree whole-heartedly. Recently, we’ve seen the development of a whole sub-industry of measuring devices to get a thumb-nail sketch, or acoustic profile, of actual rooms in people’s homes. Using sweep tone generators, room sound pressure meters, and specially developed computer software to generate acoustic models of real rooms, the new breed of room-acousticians follow the principles developed by architects and concert hall designers (Leo Beranek!) and treat listening rooms with all the methods at his disposal. They "tune your room." The newly-tuned room owners usually show us before-and-after graphs and charts of how much their rooms have been improved toward the ideal, and they expound on the virtues of this new technology. Briefly, we might say they’ve compensated for the acoustic anomalies in their room. Every room has anomalies, and room treatment is an arduous process. Even with Computer Aided Design (that cad, CAD), it involves some labor intensive trial and error; iterations and re-iterations; measurements, treatment, and re-measurements; so it costs a nice piece of change. The success stories are quite extraordinary, though, and any serious observer of audio technology would have to grant that. Some problematic rooms yield a high degree of improvement and owner satisfaction once they are room-tuned. I haven’t heard of anyone falling into a dead faint (as in those big-screen ads), but drooling is said to be quite common.

Originally, multi-channel was developed to make small rooms sound larger. It did this "trick" by controlling the time-of-arrival of the side and rear reflections at the listening spot. If, by controlling the elapsed time of the side and rear signals that were sent to appropriately placed speakers, it could mask the ambient sound in a small room with electronically reproduced reflections, then it could make a better facsimile of the space in which the recording was made. It could take the actual listening room out of the experience and replace it with an electronic facsimile of a recording venue; a night-club, a salon, a symphony hall, or an indoor sports arena. In so doing it would offer a closer approximation, say, of the Platonic ideal�acoustic instruments in their recording venue’s acoustic. At least that’s the theory.

If multi-channel was developed to make small listening rooms sound larger, and to present an image more like the original recording venue, it is by definition a "near-field system," meant to be used in smaller rooms. Happily, I think that’s where the greatest proportion of audiophiles listen; in rooms that were not designed as "dedicated listening rooms," or "listening cathedrals," but rather in rooms that serve double-duty as dens, or home offices, or TV family rooms, and maybe even living rooms. You deal with what you’ve got. And, I firmly believe, that is where the better multi-channel rig will give the best results, comparable to a killer stereo rig in a dedicated listening room. A well designed and executed multi-channel rig might serve to democratize the industry by making excellent sound affordable to most folks. In my humble opinion, mid-fi will benefit the most. People on mid-fi budgets will be able to approach the nirvana of hi-end performance, with well thought-out use of their resources.

For example, my pal Mark, a psychologist, has an office in his home he uses when he wants to "listen." He has a modestly priced rig. It’s nice, somewhat above what most PosFeed readers would consider "entry level." He surprised me with how good it managed to sound. He likes Junior Wells and his blues band, especially his latest multi-channel album, Come On In This House, Telarc (SACD-63395), and I couldn’t believe it. Good (Telarc) Sound! Through Mark’s system I heard adequate (if not killer) bass, lots of dynamics, clear and clean midrange, and highs that were "right there" if not the most refined. He went off into a standard CD recording of a Mozart opera. Stunned, I was, at how nice the standard red-book stereo recording sounded. Then he went back and played me some of the more recent Telarc multi-channel offerings: Berlioz’s Symphony Fantastic, with Paavo Jarvi conducting the Cincinatti Symphony Orchestra (SACD 60578), and the same group’s offering of Sibelius’s Symphony No. 2 in D Major (SACD 60585). (See my reviews else in this issue at www.positive-feedback.com/Issue4/telarc.htm.) Because I grew up with those two works around the family homestead, I ran right out and bought them on the way home from Mark’s house. Of course he is obsessive (aren’t we all) and managed to squeeze every last bit of performance from his rig with meticulous speaker placement, and arrangement of the sweet spot. But still, snobby me: I wasn’t prepared to hear such good sound from a six pack of Bose speakers, an Onkyo multi-channel receiver, and a down into the line Sony SACD player. You never know from where your enlightenment might come. He’s deservedly delighted.

I’ve also enjoyed the privilege of being invited to hear the Chesky corporate mastering system, and that is about as close to spare no expense as you can get. Close to state-of-the-art speakers (Verity Parsifals), and similar class (Muse) amps, with the playback side of a professional recording rig as a front end is what I’d call a "dream system." While I was visiting, David Chesky, himself, ran me through some of his masters, first in stereo (front speakers only), then in quad (front and rear speakers), and then in six-channel (front, rear, and side�55 degrees off to the sides of the front speakers, and up on tripods 7 ft. off the floor). In six-channel the sound just seemed to float there, effortlessly, in and around the furniture in the room�a sound field as palpable as if it were a real venue. It was Bucky Pizzarelli; Swing Live, Chesky JD218, recorded in a NY jazz club. The sound was a pretty seductive reproduction of an actual venue, with audience noises, glasses clinking, people talking and clapping. Of course Chesky’s room is fairly large, about 30’x15’x10’, or about 5,000 cubic feet (what would be an ample living room, as best as my faulty memory informs me), and he had enough power to sustain the whole room.

The illusion of real instruments in real space was very powerful. Closing my eyes I could feel the dimensionality of the instrumentalists and the audience. When David went back to stereo, good as it was, it was more like a performance in miniature, a kids’ orchestra inside a middle-school’s auditorium. I just had the feeling of auditioning a really nice stereo recording, rather than enjoying the illusion of being at the recording session and hearing what was going on in the club as it was being recorded. I was in fact listening in the room where the feed was mastered for production.

At its best (Chesky’s spare-no-expense system) multi-channel is glorious. At the entry level (Mark’s testing the water entry level system), it is still pretty good at what it aims to do; and between them there is a world of fine incremental improvements. Downstairs, in my listening room, I have a killer stereo system. (You’ll have to take my word on that because deadlines, and a new grandchild that just arrived, force me to go into that next time.)

Upstairs, in my office, I have a pretty damn good multi-channel system. My big rig makes stereo images so wide and deep that sometimes I have the uncanny impression I’m sitting in my favorite seat at the local symphony hall. The smaller, multi-channel rig won’t deliver the biggest crescendo quite so convincingly, nor does it do as well at reproducing the top and bottom octaves. That is not to say it doesn’t do them well: it does. But my big rig delivers those elements exceptionally well. Up to the point where I drive the speakers out of their comfort zone, the multi-channel system makes as beautiful music, sets as convincing a sound stage, and does it in a smaller, awkward room.

My "office" was a storage area because of its badly planned placement of three doors, one stairway going up and another going down, and two windows. There were no useable corners or long walls either. With a little kitchen planning book I was able to make an office out of it. As a stereo acoustic venue, it approaches the worst. My near-field multi-channel rig turns my office into a listening venue about as good as any "problem room" I’ve heard. The only thing I have to do is manually disconnect my surround channels when I’m not listening (so the dog won’t knock them over in the dark, or get himself accidentally entangled in speaker cables) and place the speakers out of the foot traffic patterns. That’s a compromise I’m willing to make. The rest of the time, like now, when I’m at my computer, it plays in stereo, with center and sub. And like I said, I get excellent sound. Great, except for the most taxing extremes. But that’s why some folks are willing to pay the big bucks: to hear even the most complex, loudest, crescendo at full cry.

So, in theory and in practice, I think multi-channel is a solution for audiophiles in small spaces with difficult acoustics, and without unlimited amounts of disposable income. Multi-channel is one way to work out the problems 80% or more of us face, and still have some money left over to buy music with. Of course there is always the cost-no-object multi-channel system to consider. Sooner or later I’ll have a go at that downstairs. For now, my way-cool, middle-priced, multi-channel rig will have to do. My purpose is to begin critical listening of new releases in SACD-Multi-Channel (SACD-M), and to compare hardware at various price points, to see for the PosFeed community if, and how well, multi-channel lives up to its hype.

I don’t expect that I’ll master this new recording medium at a glance. Being new it will require a lot of futzing with, time consuming iterations and re-iterations of speaker placement, cable switching, optical vs. analogue patch cords, etc. My former colleague at Stereophile, Jonathan Scull (mentor and friend), impressed upon me that "fairness" should be in play in reviewing gear. Each piece should be given its best shot at sounding its best. Rather than evaluating each new piece fresh out of the box with its factory provided AC power cord and patch cords, as a serious reviewer at a serious journal I would be expected to review each piece, properly burned in, and with its most euphonious associated gear and accessories. That sounds fair.

Another of my former colleague/mentors at The Absolute Sound, Harry Pearson, has impressed upon me the need to put forward my best shot at a standard audio vocabulary. To describe audio, from me you’ll have no "je ne sais quoi earth tones." I’ll try to stick to plain language delivered plainly, and I’ll lean on Harry’s work where I can. I hope you will bear with me as I’m sure to make mistakes. But, in this new e-zine format, you should feel free to email in and shout at me, "Hey Max. You futzed-up! You zigged when you should have zagged. Go back and reverse the polarity." Or whatever. I am your humble servant, after all.

So consider this a statement of purposes. Max is back!! Multi-Channel Max!