Music in the Round #1 Page 2

All of this can be folded down into two channels to give you a damn good idea of the musicians in front of you and some inkling of the nature of the recording venue, but the latter is based on inference—all of the meaningful information is coming from the front. In conventional stereo reproduction, the signals that reach your ears from the sides and rear are as much about your listening room as they are about the original performance space. The signals that should be coming from other angles are not treated appropriately by the HRTF; what we interpret about the other recorded dimensions is conjecture.

Recordist Gene Pope convincingly demonstrated this at a Stereophile show some years ago. He had recorded, in four discrete channels, a performance of voice and pipe organ in a reverberant church. Playback began with all four channels and speakers up front in a very large demo room. The sound was clear and spacious, leaving little doubt about the performers but only suggesting the performance space. Then, in midstream, he switched to two channels up front and two in the rear, the speaker positions approximating his original microphone placements. Wow! Now one could hear that the venue was a stone cathedral much longer than wide, and with resonant spaces in the rear. More significant, the performers sounded more coherent and more present. The difference was hair-raising.

But if the same sounds are all still there and all that's changed is their direction, why should this effect have been so profound? One reason, stated above, is that our brains work to translate the recorded reverberation and decay into a percept of a real space. If, in stereo, all sound comes from the front and only spurious listening-room sound comes from the sides and rear, the brain is given the difficult task of relating this information to remembered (or imagined) live events at which we experienced similar signals coming from all around us. As soon as the brain is relieved of the hard work of conjuring these experiences, the spuriousness and/or disadvantages of the two-channel experience are apparent.

I demonstrated this to myself by accident. There's little difference in the basic sound of Peter Wispelwey's solo cello between the two-channel and MCH tracks on his recording of Britten's Three Suites for Solo Cello (Channel Classics CCS SA 17102). Listening to this disc in MCH, however, I was much more relaxed and involved in the music. At one point, Wispelwey was ending a note just as I switched from MCH to two-channel, and I experienced a confusing phenomenon: the decaying note and its reverberation retreated from my room to the other side of the speakers, behind the instrument! Even though my brain adapted in seconds to again accept the two-channel illusion, the sound of that echo was patently phony in stereo. Switching from stereo to MCH never demanded any such adaptation.

If you want to hear other examples of this, get a copy of producer-engineer Tom Jung's recording of Sacred Feast, by Gaudeamus, directed by Paul Halley, on DMP SACD (SACD-09) or DTS CD (MAS CD-805); or Bucky Pizzarelli and Friends' Swing Live, on Chesky SACD (SACD223) or DVD-Audio (CHDVD222). Listen in two-channel for a few tracks, so you can appreciate just how good the sound is. Then, in the middle of any track, switch to multichannel. I rest my case.

Music requires MCH
Many of you, including the esteemed editor of Stereophile, have complained about recordings that place the listener in the midst of the performers: Listeners are supposed to sit in the audience, and musicians are supposed to stay "out there" on the stage. Generally, I agree. Most formal Western music was created with this separation of performer and listener, but there are many exceptions. Berlioz's Requiem and Boito's Mephistopheles actually specify a surround presentation (and boy, do I want modern MCH recordings of these). Traditional informal music, such as folksongs, made no distinction between performer and audience, while traditional religious services often presume that the congregation will participate in the musical responses.

MCH lets you experience that thrill of participation, of having the other voices radiate from close to your sides and project out into real acoustic space. Playing the opening of Bach's Motets (DVD-Audio, TaceT DVD 108), I was startled and thrilled by the illusion that I was in the choir, and felt encouraged to join in. You can't get that from stereo.

Today, no serious producer of recorded music can ignore MCH. Rock and pop is still a jungle in this regard, especially with the profligate use of the rear channels on most reissues. But it's getting better, and what's coming is the creation of music specifically for MCH. The advance scout for MCH-aware composition is a fascinating DVD-Audio disc, Immersion (Starkland S-2010). The adventurous Starkland label commissioned 13 modern composers to create original music with the specific understanding that it would be delivered in 5.1 channels. Some of the pieces transport the listener to strange places both natural and unnatural, some superimpose experiences that could not otherwise be combined, and others expose us to instruments whose spatial properties would be crushed if presented in only two channels. All of the music is fascinating in MCH. In stereo, it doesn't make nearly as much sense.

Give the people what they want
Forget us audiophiles—we're too few for commercial consideration by the major record labels. And forget those who are happy with bandwidth-limited MP3 files streamed from the computer into their implanted earphones. I'm talking to the many middlers who buy multichannel home-theater systems for watching movies. Ask any retailer, whether high-end or big-box, and he'll tell you that, along with plasma TVs, home theater is what's moving. These buyers paid for their rear channels and subwoofers with valuable dollars and whispered concessions to spouses in order to hear the surround effects encoded on DVD movies. When these folks buy a "record," they expect to hear something out of every channel or know the reason why.