Rich, following your logic, how do you propose those who own omni-directional speakers like MBL and German Physik treat their rooms? By shrouding the front 1/2 in absorption?
I propose they experiment and find what sounds best to them in their system and room. We all have different ears, rooms, and psychological expectations of what music should sound like, so you really have to do what works for you. As I said, I prefer to get as accurate a rendition of the recording as possible.
I do seem to recall (and perhaps another member that was there can chime in on this) that when I heard the MBL setup at RMAF a few years ago, they had the entire front wall behind the speakers covered in drapes. This was in a very large room too. So it isn't too far out of the realm of possibility to consider that Omnis may benefit from front wall absorption in certain situations.
Also, all recordings are a facsimile of the actual event and most instruments are not producing sound uni-directionally. They radiate at least 180 degrees, some 360. Listen to a live band or better yet an orchestra and you'll hear how all recordings are far from sounding like true live music.
Yes, all recordings are nothing like live music no matter how much we want to try to make them seem otherwise. We have debated this topic much on this forum. Even with live orchestra, the soundstage and imaging is very different depending on where you sit (in front you may have pinpoint imaging and huge soundstage width, but little depth; in the rear of the hall you may get very diffuse imaging and a smaller soundstage width but lots of depth). I never said I was trying to replicate true live music (as ultimately I think that's a pipe dream and not even necessarily desirable as lots of live music sounds like crap for various reasons). What I said was that I am trying to replicate the sound of the recording as the recording engineer intended. Not true to life, but true to the source.
This is an important point. Stereo imaging and sound staging are an illusion, created by the recording engineer using various recording and mixing techniques. Some recordings have a great soundstage, with lots of width and depth and pinpoint imaging, and some don't. But all of this is achieved through the magic of the stereo mix created by the engineer.
Every speaker is a compromise. All have their good points and their limitations. But lets be clear on this: The front wave of an ML is the musical signal. It contains all of the musical information and spatial cues in the mix. If you listen to only that, in an otherwise great system and room, you will hear the imaging and soundstage width and depth that the recording engineer baked into the mix.
The rear wave of an ML is a by-product of the speaker design. It contains all the same information (out of phase), which is then reflected off the front and side walls and returns to the listener after the original signal. If the speakers are properly positioned, the brain perceives these later sound waves as a reverberation which creates a sense of depth and spaciousness (what a lot of people call the "ambiance" of ML speakers). This was not included in the mix or ever considered by the engineer (he doesn't know what kind of speakers you are using). It is simply an anomaly of the type of speaker and how it interacts with the acoustics of your room (not much different than a bass mode in that respect).
It also really isn't much different than the DSP programs in my old Yamaha receiver that would add reverb to the signal to mimic certain settings, such as a concert hall, a stadium, or a church. It can sound really cool. I used to put on a gregorian chant cd and put it on the cathedral DSP setting, and wow did it sound cool. On a solo acoustic performance, not so much. But the point is that it is fake. It is added. It is not part of the intended sound of the recording.
If it sounds good to you on your speakers in your room, that's great. I recommend to anyone that they go with what they like. But if you think the exaggerated sense of depth you hear is an accurate rendition of the recording, you are fooling yourself. If you want proof of that, play a mono recording on your system. I expect you will still get some of the spatial cues of depth and spaciousness (not as much as from a stereo recording, obviously). But you will get some, and you shouldn't get any in a mono recording. You get some because it is a byproduct of your speaker setup and not really an accurate rendition of the recording mix.
By absorbing the back wave and listening only to the front wave, you hear the recording exactly as it was intended, with all the attendant spatial cues. That is what I get in my system. The whole point of this long explanation is just to emphasize that absorption of the back wave of ML speakers is preferable for lots of people in all kinds of situations and doesn't really pose any downsides other than the loss of a false sense of ambiance.
My apologies to the O.P. for completely derailing the thread, but I have thoroughly enjoyed having the discussion with you sb6. Hopefully someone will get something out of reading it. Happy Thanksgiving!!!
