Meridian Digital Theatre surround-sound music system Page 6
Meridian's 861/DSP6000 proved a superb two-channel system, and the addition of a center channel (Trifield) was almost always an improvement. But what happened when, using normal (nonencoded) two-channel sources, I added the two remaining?
First, I synthesized a surround channel and added it to an L/R or Trifield front, but all that accomplished was to make the sound blowsy and indistinct. Sure, I was more immersed in the soundfield, but that soundfield was far from realistic, and the effect was unpleasant and unmusical. Adding the rear channels to Trifield meant going from palpability to vagueness. I fiddled a bit with the relative level of the rear speakers, but always found the optimum level to be the minimum level.
It was a much different, if more complex, story with discs that were recorded with surround or rear-channel information intended for extraction from the two-channel mix. With Dolby Surround discs, such as Strauss' Also sprach Zarathustra with Lorin Maazel and the Bavarian Radio Symphony (RCA 68225-2), there was a welcome sense of "place"; I felt closer to and more intimately involved in the music. This effect was so enjoyable that I even sat through all of Andrew Litton and the Dallas Symphony's new recording of Mahler's Symphony 2 (Delos DE 3237), even though I find the performance torpid and uninspired. Mahler's massive forces were so much less constrained with Pro Logic decoding.
I used Delos' DVD Music Breakthrough (Delos DV 7002) for many auditions because it offers both Dolby Surround and Dolby Digital tracks. When I listened to the Dolby Surround program in two channels, the listening window was as wide as the room but far away. Orchestra and soloists were arrayed widely, but extended back from the plane of the speakers. Violins had a distinct edge, but reverberation and decay endowed each instrument with an aura of ambience.
I then switched the 861 into Pro Logic and the change was amazing. First, the instruments seemed less widely spread out. However, they were more "naked," less cloaked by hall ambience, and the violins were less edgy. The best part was that the listening window was now much closer to me; in other words, I was "seeing" into more of the concert hall. At no time was I distracted by inappropriate signals from sides or rear. Still, I was not so much "inside" the hall as standing on its threshold.
An older technology for achieving a similar end is Ambisonics. These recordings are made with a single, "Soundfield" microphone and are usually labeled "UHJ encoded." So far as I know, only Nimbus Records continues to regularly offer such recordings. Since I am a devotee of the Hanover Band's recordings on Nimbus, I was anxious to hear them, for the first time, properly decoded. I popped in the Band's CD of Weber overtures (Nimbus NI 5154), which has afforded me great pleasure over the years, expecting to be overwhelmed.
I wasn't. Certainly, as decoded by the 861's Ambisonics mode, Nimbus' characteristically ripe reverberation was now more enveloping and natural, but there was a loss of immediacy with the instruments, which now were almost dwarfed by an apparently immense recording venue. One can adjust the 861 to simulate different seating positions with Ambisonic decoding, but although these adjustments changed my proximity to the instruments, none eliminated the dominance of the reverb.
But all was not lost. The Test Discs from Hi-Fi News & Record Review include several UHJ-encoded tracks, both of music and of sound effects, which were greatly improved with proper decoding. Mike Skeet's infamous garage-door slam-and-kick routine (HFN 003) was spine-tingling---I felt as if I'd been trapped in that garage. The small "Feeny Poppers" cannons (HFN 015) could be heard to have been placed in an obliquely receding line as they were fired in series.
Finally, I recalled that the Cowboy Junkies' The Trinity Session (BMG 8568-2-R) had been recorded with a Soundfield mike. What a coup! This recording needs no introduction, but if you haven't heard it decoded, you don't know how eerily realistic it is. With the 861 on Ambisonic and five DSP speakers, I was inside that Toronto church on that November night in 1987. All the subtle little sounds (air conditioning, footsteps, incidental instrument noises, etc.) that audiophiles detect with relish were not only revealed, but were part and parcel of the band's enhanced presence. Add to that the greater immediacy of the voices and instruments, and although I've heard this disc perhaps too often, I was hooked into listening to all of it again. Although there may be controversy about whether the Soundfield mike was actually in Ambisonic mode at this session, it was the most heartening indication I've heard so far that multichannel could be more than a gimmick for audio.