Space...the Final Frontier Letters

Letters in response appeared in Vol.17 Nos.6 & 7, June & July 1994

Appalled by Gordon
I was appalled by J. Gordon Holt's "Space...the Final Frontier" in March. As an audio manufacturer, I disagree that there is no room for more than incremental improvements in two-channel stereo. Components are breaking new ground at a rapid pace; this is no time to give up the ship. Besides, are you guys ready to change your title from Stereophile to Surroundophile? Doesn't that just roll right off your tongue?

Gordon complained in his "Space" article about designers deviating from a flat frequency response to make their loudspeakers sound their best in stereo. It wasn't that long ago that J. Gordon Holt boldly proclaimed "Down With Flat" in the pages of Stereophile (Vol.8 No.4, p.5), advocating exactly the type of frequency-response shaping he now condemns.

Gordon also stated that the space found on stereo recordings is the result of comb filtering from room reflections that are out of phase; he also stated that many recordings have no depth whatsoever. Room reflections, whether off the front wall or any other wall, can take a great many paths, so there will always be random phase information delivered. A room does not become an anechoic chamber for some recordings but not others...The fact that the soundstage changes with different recordings, as Gordon acknowledged, is an indication that the perceived soundstage is not an artifact, but is in fact a representation of the original musical event...Gordon's hypothesis also fails to satisfactorily explain why, on many recordings, you can hear the size of the recording venue during the silence before the first note has sounded.

Since we perceive direction, distance, depth, and height as functions of the information sent to our brains by our two ears, why should Gordon dismiss the possibility of two microphones being sufficient to capture all the necessary information, and two channels being sufficient to reproduce that information? Of course, Gordon and John Atkinson are correct regarding rear sounds being reproduced in front of the listener, but so what? Is this any less realistic than those quadraphonic recordings that placed the listener between the performers (a location unoccupied during the performance)? It may be fun, as Gordon said, but this type of source material doesn't even attempt to be realistic. If this is what someone enjoys, far be it from me to tell him he's wrong to do so---but it doesn't make a two-channel system obsolete.

It's also true that most people have a fixed amount of money they can afford to spend on a sound system. For such people, the greater the number of channels, the lower the quality of each of those channels.

While I will not deny that properly applied surround-sound has merit for some applications, two-channel stereo still deserves your support. Two-channel stereo would not be where it is today without J. Gordon Holt and Stereophile; but where would Stereophile be today without two-channel stereo?
---Alan Rauchwerger President, Virtual Image Audio, South Hackensack, NJ

Gordon is a gem
Gordon is a gem. At last, a comprehensive essay on why multi-channel surround-sound should be the audio standard of the future ("Space...the Final Frontier," Vol.17 No.3, p.60). And what a superlatively written piece.

I'm totally behind you, Mr. Holt, because I agree with your observations, especially in regard to imaging and staging. Multi-channel sound (surround or frontal only) imaging and staging are so far superior to conventional, two-channel, two-speaker imaging and staging, it's a wonder how reviewers and audiophiles can go ga-ga over the latter. These chaps must possess a superior adaptive mechanism that enables them to totally suspend disbelief whenever they turn the audio on and the lights off; they do it so well that, despite the obvious and glaring spatial distortion of conventional stereophony, they can believe that they have been transported to the concert hall. Any child should be able to point out to them the emperor's clothes.

As for John Atkinson, I wish that, whenever he speaks up for conventional stereophony and against multi-channel frontal and/or surround-sound, he would try to recall the feelings he experienced when he first heard a well-set-up, full Ambisonics demonstration in England in his younger days. This surely is a classic case of "stick-in-the-mud" audio mentality.
---Yip Mang Meng, Singapore

Bravo, J. Gordon Holt
J. Gordon Holt, bravo for your article on surround-sound (March '94, p.60). Four-channel recording/reproduction is the obvious and inevitable evolutionary direction of audio reproduction. This change will erase and rewrite the design criteria for the next generation of audio components; the listening experience will be elevated from the listener observing the music from an outside window to the listener actually attending a musical event. I don't know about you, but I'd rather my system made me feel as if I were in the audience instead of looking through my expensive hi-fi window at the performance.

There will be a great resistance in the High End to this inevitable change, especially from those who manufacture audio gear that is now considered cutting-edge, as much of it will be unsuitable for re-creating a realistic 360 degrees soundfield (ha!). My friends, please embrace and encourage this coming forward leap in the listening experience. I'm sure that when these concepts come to fruition, the audio industry will experience significant growth as people like us demand to experience this new level of audio reproduction.

While JGH explained that we could extract the rear-channel ambient information from our present CDs and LPs by left-right subtraction, he did not describe how this can be achieved by any red-blooded audiophile with a single stereo amplifier: Simply hook two surround speakers [with their terminals wired positive-negative-negative-positive---Ed.] across the amp's two positive loudspeaker terminals. (Note that the front speakers are wired in the normal fashion.) A resistor or potentiometer can be placed anywhere in the rear speakers' connection loop to control their output level. In this [Hafler] setup, the rear speakers' output is the (mostly) ambient information JGH referred to.

Thank you, Mr. Holt, for spreading the word.
---Justin Graves, Dayton, OH

JGH is right on
J. Gordon Holt is right on with his March '94 article, "Space...the Final Frontier." He is reinforced in the same issue by Corey Greenberg's Follow-Up of the NHT 3.3 (p.135), in which CG recognizes the importance of increasing the ratio of direct:reflected sound. This is what JGH is saying: that the "reflected" sound should be replaced with surround channels. In my opinion, the high-end community is reluctant to embrace "surround-sound" for the same reason that it's overly taken with minimonitors: They can't bring themselves to accept the fact that lifelike sound reproduction requires big speakers, and big speakers don't sell (especially if you need four of them!).
---Tom Graham ,Fullerton, CA

The real surround problem
J. Gordon Holt's article on surround-sound music systems (March 1994, p.60) was excellent.

The real problem for four-channel music systems is software, not hardware.

If record companies cannot take music recorded in the past (the Beatles catalog, etc.) and reprocess it as four discrete channels, I, for one, will never consider the purchase of such a music system.

No, I do not want 70% of the benefits of a compromised music system. I want all or none of the benefits.

The music that was produced in the past gives me much greater pleasure than the music that is now being made.
---Joseph Kronberg, Cambridge, MA

Thank you, Mr. Holt
Thank you for Mr. Holt's article in the March issue about "surround-sound." His comments are completely consistent with my own listening experiences. I own an ADS model 10 "acoustic dimension synthesizer," which I purchased in 1978 during the infancy of digital technology. The unit is very flexible, allowing individual selection of "ambience extraction" and/or "ambience synthesis," including separate reverberation and time-delay controls. Moreover, four separate rear channels produce a more uniform ambient field than only two could provide. The well-written owner's manual explains that, ideally, most ambient information should be "recovered" with no need for added "synthesized" reverberation when extracted from the best recordings.

After living with a multi-channel system for many years, I would be unwilling to relinquish its virtues even while allowing for the limitations of my somewhat antiquated equipment. (Obviously, modern digital processing circuits would produce less distortion and noise.) The point I wish to make, though, is that the system effectively reconstructs an expansive three-dimensional "sonic aura" that transcends the constraints of the "soundstage." The full impact may be best realized when the experience is abruptly ended by turning off the side channels. Suddenly, the vast image collapses, and Carnegie Hall implodes into a gazebo.

Mr. Holt believes that many audiophiles have not become committed to surround-sound because their initial experience has been disappointing. His point is well taken, but if we apply equal rigor and persistence to setting up a surround system correctly, as we always have with more familiar components, the results will improve accordingly.

There is no doubt that multi-channel technology introduces additional variables which must be managed properly, but the potential rewards are well worth the effort.
---Bruce M. Everett ,Odessa, FL