As promised (threatened?), I've finally had a few spare hours to work up some OmniMic measurements of my Pro calibration. Let's just say that the OM is finding some dips that weren't particularly obvious on the Pro "After" curve. FYI, both of my HSU subs were at 0 phase, and run with ULF trim of 50 Hz as per Dr. Hsu's advice on the ULS-15 thread, and the L/R mains were crossed at 60 Hz.
I ran the curves with sine sweep (track 2), only the mains and subs on, and all channel stereo. The blended curve setting @ 5 msec and 1/24 octave smoothing were also in play.
First up is the "Pre" Audyssey curve:http://imageshack.us/photo/my-images...osurround.jpg/
There's room gain driving the curve up until about 40 Hz, and then dips at about 46, 59, and 90-95 Hz. Fairly hideous, huh?
Here's what Audyssey did:http://imageshack.us/photo/my-images...osurround.jpg/
The resulting curve is flatter, but it doesn't seem that those dips were addressed.
However, I tried the 'phase' adjustment on the subs on the initial Audyssey run. The next plot has the left sub only set to 180 in purple, and a curve with the right sub only set to 180 in green, with the 0 phase for both subs in red:http://imageshack.us/photo/my-images...rroundand.jpg/
It seems that either phase switch is helping with the 46 and 59 Hz dips, and making the dip @ 90 Hz worse. I'm also getting different handling of the "room gain" < 20 Hz, with the 0/180 version of the plot looking like it's making the lower frequency flatter. However, I have more of a peak where I had the dip before.
What's the advice of the Pro gurus? I'm tempted to rerun Audyssey with the 0/180 left/right sub plot before I do anything else. But what about that 90 Hz dip?
Note that I don't have my powered center included right now. I'm still waiting for my vaporware Lovan standalone center stand to liberate the center for better powered bass and a 60 or 80 Hz crossover.
Chris: this is what you've been waiting for