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Ambiophonics |
Surround Sound Dun Rite Dear surround sound devotees! Most of you know me as the "music from two speakers only, thank you!" guy, but last week, I had an experience that was just about enough to convert even me and I want to share it with you all. A few weeks ago, I was talking to fellow forum member Len Schneider on the telephone and the recent Corey Greenberg article entitled "Stoogephonics" (or something like that) came up in conversation. As it turns out, Len is acquainted with the creator of the system that was subject of that article. Len was mildly upset at the lampooning of Mr. Ralph Glasgal and his "project" because Corey had never heard it but chose to make light of it citing its impracticality. After telling Len that I would love an opportunity to hear such a rig myself, Len promised to try to set it up. Well, he did and I heard it last week. Len and I arrived at Mr. Glasgal's home (and what a home it is!! Yikes!) and were taken immediately to his listening room/lab. The first thing we were treated to was a listening session on a system consisting of a small amplifier, an obsolete Kodak CD player and a pair of Radio Shack diminutive Optimums Pro 77s. The simplicity and "un-audiophile" nature of the system was part of the point here. The speakers were placed right on top of the CD player with only about 4 or 5 inches separating them. The chair was placed several feet in front of the system. He played a home brew CD of a Buxtehude cantata that left me flabbergasted. While the speakers were there directly in front of me with almost no spread, I was treated to a sound stage that extended way out to my right and left. While nice, I have heard this kind of sound stage before, so that's not what flabbergasted me. It was the sound staging and (in particular) the depth of the image that got me. I had NEVER heard such a deep and clearly defined sound stage before. NEVER! I heard (saw!) clearly defined layers of depth, almost as if I were looking at a hologram. I can't emphasize the word "clearly" enough here. While as a matter of habit, I did close my eyes when the music started, it didn't take that much concentration to put together what was being portrayed before my eyes (ears). As I said, it was the most focused sound staging I have ever heard. Amazing. Next on the CD player was a "pop techo" piece I was totally unfamiliar with. While I cant say I enjoyed the musical content all that much, I was again left speechless by what I heard. Again, wall to wall sound staging. Again, ribbons of holographic type layers of depth. But this time, I heard incredibly depictions of height. I heard sounds presented of wildly differing height on the sound stage. Up, down, in the middle, all over the place. Amazing again. After that, we were treated to an acoustic gramophone recording circa 1917 of a solo soprano on an all acoustic player and then it was dinner time. Dinner was nice, but I wanted to get to the main subject of Corey's article! So back into the sound room we went. The room was VERY large. I would guess it to be around 30' front to back, and 27' wide. The ceiling?? Uh, it was three stories up! I told you it was large! There it was, the impractical beast as Corey had described it. Speaker-wise, it was a pair of VERY large Sound Lab electrostatic panels . These speakers were actually pointing in the opposite direction though. The panels, like Martin Logans, are curved (to improve dispersion) but as Mr. Glasgal was trying to completely control dispersion, we were listening from the custom curved "concave" side of the speaker which beamed the sound at us like a laser. This was the only part of the system he was trying to control in such a complete way. Flanking the speakers was a pair of Duntech Sovereign speakers. These were used as the first pair of surround speakers (hey! One must make use of what speakers one has!). They were to the outsides and behind the main speakers and were leaning over to their sides, I would guess they were leaning at about a 60 degree angle. Working their way to around to the rear of the room, were more speakers. Leaning at about 45 degree angles toward the rear of the room. At the side of the room, were a pair or Acoustat 1+1s. These are about 8 inches wide, by...oh, 7 feet tall electrostatic speakers. Mirror imaging these 1+1s were yet another pair of the same speakers. The tops of the two speakers met at the apex forming a "/\" arrangement. The furthermost rear pair of speakers were Carver ribbon speakers. Mr. Glasgal would have loved to have another pair of 1+1s but couldn't find a pair, so the Carvers being tall and dipolar would have to do. Anyway, the Carvers completed the speaker array. As you can probably visualize, the 12.2 surround speaker array, including two Sunfire subwoofers, pretty much blanketed the walls around me. Unlike a series of speakers hung on walls as we usually think of them in surround sound, the speakers were arranged so that they formed a belt of sound around me. The listener is immersed in a directly radiated sound field since the rear wave of the dipole speakers is absorbed by the room treatment. But I haven't gotten to the strangest part of the set up! The Barrier! The most important part of the system is the Barrier. As in the earlier demo, the big Sound Labs were placed in front of me with no spacing between them. They were almost side by side. Between them, placed perpendicularly was a wall of sorts. This wall started some three feet from the speakers and came at me and ended a matter of a foot or so from my face! The wall is an acoustic barrier designed to keep the right ear from hearing the left speaker and the left ear from hearing the right speaker. There are very specific reasons for why the speakers are placed right next to each other but I don't think I'll have space enough to go into it here. There have been a variety of attempts to achieve the same thing this barrier does. Polk SDA speakers use a second set of drivers to cancel out inter-aural cross talk, Carver's Sonic Hologram Generator did the same thing through electronic means. I've heard them both and can tell you that they couldn't do what the real barrier did. Even with the surround array turned off, I was treated to a most amazing sound stage. As with the smaller set up, even though the speakers were right in front of me, the sound stage extended way out to the sides. Specificity was amazing as was sound stage depth. After a series of demo pieces, Mr. Glasgal put on an organ recording. It sounded fabulous. Sound staging was exactly as I had been hearing it. Wide and deep. But guess what? This was a mono recording!! Of course, the organ was right in front of me, but the illusion of space surrounding it was as convincing as were the stereo recordings. Now, Corey was right about one thing. For most of us, this set-up is completely impractical. But hey, if you have the means and the room, you should hear it! But, what Corey got wrong was the value of such a system as a research tool. Without the full blown system, the experience I had on the smaller system would never have been. Mr. Glasgal has done extensive measuring and has succeeded (I think!) in his ability to encode any naturally miked CD with what it takes to recreate the experience from two closely placed speakers (and no barrier!). As I mentioned, I heard two CDs, Mr. Glasgal was disappointed that he had not received a third from his man in Wales who actually does the encoding and wrote the required algorithms. What he does is download the digital info from the original commercially recorded CD into a computer. The PC then encodes this data with the barrier algorithm and then writes it to a CD-ROM. So, now there are two ways to enjoy the fruits of his labor, you can set up the speaker array with barrier, or you can use the encoded CD. He is working on yet a third way. It is possible to load all of this into a real-time CD processor but so far they have not been able to do this. One of the reasons I'm telling you all this is because, in an effort to let people know what he is up to, Mr. Glasgal will be demonstrating this technology at the high 98 in Los Angeles in Mid June, suite 840, (along with SoundLab and Echobusters). I highly suggest you check it out. John |
