Meridian,

With no center channel speaker (phantom center) Trifield is definitely operative on my My 568.2 (Both build 2.12 and 2.5 beta 9) and different than Stereo. At a minimum, the rear channel operate in Trifield, recovering ambience.

I have tested the width adjustment on the 568.2 using NO center speaker and using a center speaker. I used recording that had exhibited an extreme level of change (in previous firmware versions) when width was adjusted, and now they exhibit NO change. I tested this phenomenon with and without a center using both firmware versions listed above.

So, something else has changed that is significant. As I stated in posts above, this probably happened when I had my 568.1 upgraded to 568.2 - I guess I was simply looking to find out if anyone knows when and why the change occurred. I didn't follow up on it at the time I upgraded beccause I wasn't using a center channel at the time, and figured that width, like depth, was not practical without the center speaker. Upon adding a center channel, I was surprised to find that it still didn't work.

John

Main system: Cable, Apple TV, HD621, G68D, AC11, 218, DSP7200SE (L+R), DSP3200 (L+R Rear)
2nd system: Cable, Apple TV, MC200, HD621, 568.2, M3100 (L+R)