What will the Trinnov Optimizer do for 5.1 HT Audio?

Is it a self calibrating process similar to setting the reference level on a 990?

Will it make a big difference in playback for 2 channel and 5.1?

We don't know - no one has ever heard it in a consumer product.

As I understand it, Trinnov has more in common with Audyssey MultEQ or similar room correction software than with the basic auto setup offered by the 990. It sets distances and channel levels, much like the 990's auto setup does, but then it also applies audio processing separately to each channel (EQ, etc.) to try to compensate for room effects. The benefit of existing EQ solutions is a matter of much debate. Some feel that it is a "must have" feature that makes a huge difference, while others feel that it is a compromise work-around to proper room treatment that offers limited to no real benefit. The more advanced EQ solutions tend to land closer to the former than the latter (more "great feature" and less "useless feature"), but much like the SMS-1 the benefits will depend on how much is wrong acoustically with the space to begin with. Trinnov is also supposed to be able to correct for sub-optimal speaker placement, although I can't speak to the details of how it achieves that (haven't figured it out, frankly).

You haven't been able to figure it out because it is impossible to do in any meaningful way. There are a lot of "cheats" that can be done, but no amount of signal processing on earth can figuratively "move" a speaker from a sub-optimal position to a "optimal" one.

From the literature, it appears they are "mixing" between the 5 or 7 channels instead of sending them discretely to the correct speaker such that , say for a situation where your rear left surround is to far back, a small amount of the signal for that speaker would be sent to the left side surround so that the "image" of the sound would come forward from the actual speaker position slightly.

So they create virtual speaker locations using your actual speaker. It will work well in situations where your speakers are off ideal positioning in the horizontal plane, but physics ain't gonna change where one speaker in the system is too high.

The Audyssey in my system had a pretty noticeable effect. I have a 6.1 setup (two rear surrounds, the 6 comes from going phantom center, not single rear channel), but my speakers are placed basically in the exact recommended symmetry and position, so it is mainly correcting for acoustic issues of the room, not placement.

That said, it definitely improved the surround experience in my system. I ran for nearly 7 months without it, so I was well acquainted with the Onkyo 885's sound in my setup before I ran the correction and began using it.

It sounds like the Trinnov is at least a comparable system, so unless your room is spot on for spec and treated with very good acoustic control, I would bet most would find it a positive feature at least for HT. On SACD, I disable all the processing.

Basic old skool calibration would accomplish the same thing, ensuring that the SPL and delay (and by extension imaging) of each speaker is equal.

How so? Simply balancing the levels without remixing the channels so that portions of the signal for one channel are steered to another would not have the same effect.

Something like Logic 7 that had very good steering built into its processing, yes, but simple level and delay would not do this. You don't want each speaker to be equal to correct for bad positioning, you want each signal to be equal, and it may come out of two different speakers instead of the one it was destined for to do that.

A little OT, sorry...

While I'm looking forward to toying around with the Trinnov, I'm also amused by the disconnect between video and audio perceptions by HT fanatics.

They'll whine seven ways to Sunday if some color timing choice doesn't fully "represent the intentions of the director." And yet they'll post-process the soundtrack up the ying-yang without a second thought.

Trust me, the guys who engineer and master film soundtracks are artists the equal of anyone working on the film. Their artistic intentions are essential to the quality of the film and also deserve to be reproduced as they intended.

You do point up a weird disconnect. I think nobody really cares about good reproduction of sound any more.

You guys are right.
For me, anyway, TV, movies etc is and always will be secondary.