Couple of weeks ago we made some changes to the house and living arrangement. I was unable to figure out a workable solution for the 7.1 system I run (Denon receiver, Infinity Speakers) which I love. I'll need to have someone come and rewire the house. Since this will probably not be for a few months, I went ahead and got the YSP 900 as a "stop gap" solution until I can go back to my full setup.
After using this for a few weeks, testing, retesting, etc...I have come to the following conclusions.
Negatives-1. You can't expect to fully replace a 5.1 system...certainly not a 7.1. Having the sound actually anchored to specific spots in the room is just plain better.
2. On some broadcasts, you can get a hollow sound that is distracting. You can minimize this with some of the various settings (specifically some of the manual Beam settings).
1. It does do a surprisingly good job of creating a surround sound atmosphere. The setup microphone was a good start, but after some careful listening and tweaking in the manual setup, I was able to define some pretty clear surround fields. I would argue against anyone saying it creates a "simulated" surround effect. The sound is not simulated. The sound fields are decoded by the YSP and, using the setup of your room (walls, furniture, etc...), it is reflecting the specific surround field to the correct area. If you have done the setup correctly (auto or manual) and run the test tone, the test noise will travel from FL, C, FR, SR, SL, SW and you can hear it.
Again...I am in NO WAY stating that this matches my 7.1 system and I will be moving this into another room as soon as we can rewire the house. I am saying that it does legitimately do what is advertised. The room is fairly large and not exactly ideal (ie...4 square walls), but with some effort, I have a surround setup that is sufficient until I can get the system back up. I imagine in a smaller, ideal room it would perform even better.
As a test, I ran the Matrix HDDVD bank lobby scene. This is an extremely complex scene soundwise. Music, guns, shells, breaking tile, constant panning...and I have watched this many times on my 7.1 system. Given my familiarity with how it should sound, the YSP does an admirable job. The tile that breaks at the end of the scene is clearly on the far left. The shells coming out of the guns are clearly behind me to my left and right as they should be. The background gunfire is going on all around me.
Honestly, I purchased it with the full expecation that it would dissapoint me, that I would bring it back, and that it would convince me to have someone come out and rewire immediately (which I'd rather not do until the wife is CERTAIN that things will stay as they are...this is a constant battle in my house). I have been pleasantly surprised and am content (at least for a couple of months) to use it.
....just make sure you have a sub with it.
Hope this helps.