|Jim, tell us about your experiments with speaker placement and how you found the PZCs allowed you to spread your speakers much wider, closer to the side walls, yet provided clearer phantom center speaker imaging.
Prior to owning PZCs, I have owned ASC Traps, RoomLenses, the pillow type "RoomTune" products including their floor standing Deluxe Tunes and Bass Tunes. My goal with speaker placement has always been to have a stable, wide, deep soundstage with a wide "sweet spot" where more than just one or two people would have total enjoyment of the audio or video experience. There are many speakers around that can "disappear" in a room, but there are very few rooms that will really do these speakers their due justice. I found that all of the alternative products I tried did make some difference, but none totally allowed the boundaries of the room to virtually disappear. For many years, I experimented with using three speakers across the front, but the surround "software" and circuitry available did not do justice to the surround experience because there was too much "blend" of the sound to the center channel. Pans were not as smooth as they are in real life, nor as "realistic", even when using three identical speakers across the front.
At one time, I had 2 RoomLenses, 4 Deluxe Tune 4' Panels, 1 Bass Trap and 4 Corner Tune products in my home theater (along with 2 subwoofers). After the PZCs were announced and I had gained experience with them in my audio system, I replaced all of the previous products in my home theater with just 4 small Mini Corner PZCs. The home theater room always had boom on explosions and must have driven my neighbors crazy.
I then replaced all my speakers in the theater with tunable speakers and 1 tunable sub. When I installed the small PZCs (11"H x 6 1/2"W x 4 1/4"D), the walls, floor and ceiling of the theater "disappeared" sonically. At that point, I moved the speakers very wide apart (to the point where most people would think there would be no center fill at all) and did away with the center channel speaker. With only very slight toe-in, I found that not only was there more than sufficient center fill, but the soundstage in the theater was spread completely across the front of the room with sounds produced with the right "size" as in real life. Dynamics improved as well as pacing of music. I could control the acoustics so well that on a "live" DVD concert, I could make the acoustic of the room sound exactly like that of a live performance with all the ambience of the original theater. The speakers completely vanished. Bass quality and bass quantity also improved with the "better" subwoofer in the room and it doesn't seem to matter very much where I place it.
Once I was performing some work on the floor about 4 feet directly in front of the right front speaker in the theater. I had a movie playing at the time and what I found was that the center image was still anchored at the middle of the screen (32" direct view) and I could not hear the speaker that was directly in front of me unless I put my ear about 12" from the speaker. That proved to me that a center channel is definitely not needed if you have correct speaker placement and GOOD speakers. At any position on the rear wall of the theater, the center image is anchored properly and the soundstage does not move as you walk from one side of the rear of the room to another. Pans are better and more natural sounding since there are 4 identical speakers in the theater. I also found that, with good acoustical treatments, placement of a subwoofer becomes a lot less critical and that it is possible to produce sound pressure levels and dynamics that approach "real" if 1) you have a good subwoofer that sounds good on music and 2)the subwoofer is fed with good electronics. I say "good on music" because I have found that if a subwoofer is not capable of producing good sound on music, it will never perform optimally on home theater tracks. In other words, "roar and thunder" do not make for realism -- with a non musical sub, what you get are unrealistic sounding explosions and unrealistic sounding bass effects, etc. although you may have a lot of bass "volume". But, volume does not always equate to "real".
So, along with good acoustics, the theater experience will suffer if the speakers are not up to the level of the "room" and electronics. There is a good general rule to follow when it comes to acoustics (and speaker placement) -- if voices sound "natural" in the room, all other reproduced music and effects will sound good in that room. When you dampen a room, just make sure that you do not overdampen it to where voices sound "dead" or muffled because if voices do not sound natural, neither will any recorded material.
So, I find that speaker placement is important, but without all the other ingredients being present the results will only come up as mediocre.
Steve, I think you are one of the true fortunate beings on the planet to be able to plan and build a dedicated theater. I saw that you said you went directly with PZCs without trying conventional treatments. Well, take it from someone who has tried just about all the conventional treatments available (I did not list all the things I've tried and experimented with), be thankful that you did not have to go through the trial and error of trying to get things "just right" and never quite succeeding. I think Tom's description of what he hears in his room says it all because that is exactly what is heard in my 2 audio systems and my separate home theater -- the same experience of sound coming from everywhere but the speakers. And, the sound is "coherent", focused and natural. But, again, it takes GOOD speakers all around in your theater along with placement, good electronics and good acoustics.
Best wishes, http://www.avsforum.com/ubb/cool.gif