I've done some eight-position Audyssey Pro runs for my Denon 4311, and after my last run, I have a few questions about how I can best refine a full Pro calibration. Since I've got dual subs, I want to maximize my time, since as per AustinJerry's findings, adding additional positions to a previous calibration file for a dual sub output setup may be problematic - I want to get the best 8-16 position run I can. Hopefully this isn't too basic a question for this forum these days:-).
To recap, I've got a 24 x 17 carpeted room, with Mythos ST fronts, CS 8080-HD center, Gem XL stands, and dual HSU ULS-15 subs. The Gem XLs are raised on 42" stands in the left and right corners, flanking the sofa we use as MLP, and the HSUs are located to the left and right of the sofa, on the floor. I did the 75 db level matching of the HSUs, which put them at about 10:30 on the volume (almost identical to what they were when I ran AS-EQ1 with an SC-57 based system last fall).
The Mythos ST are at 12 volume, as are the CS 8080. With the AS-EQ1, I was able to get a flat predicted curve from about 15 Hz on, having the Mythos slightly hotter (closer to 1-1:30, but I turned them down slightly to have a more neutral baseline). The curve I'm getting now isn't nearly that "flat" below 120 Hz.
I will add that we have one of those infamous glass tables near the MLP, but it's below the height of the center. I also took care to have the mike boom angled so it's not in the line of path of the speakers, and do eight measurements within the axis of the L/R speakers, and at or near ear height, distributed evenly to the left and right of the MLP and three seats on the sofa. Otherwise, I've got the standard recommended settings: LFE only, LFE pass filter of 120 Hz, etc.
My before-after curves are attached. If I'm reading them right, there's some issues with the center and surround speakers in particular below 100 Hz, and and the big hump above 100 Hz for the two surrounds that Audyssey is struggling to deal with. I got the standard Full/40/60/80 for the Mythos as crossovers, but the recommended crossovers for the center were 120 (!)/110/90, which sounds surprising with a powered center at 12:00.
I don't mind the 90-110 Hz crossover for the Gems, but I'm concerned about the less than flat response around the crossover region for both the center and surrounds on the 'after' chart (it was even worse when I tried the 110 and 120 Hz crossovers for the Gems; crossing the plotted -3db well above 200 Hz if I follow the main X axis label points for the heavy lines on Pro). To my ears, the center sounds a little brittle on music (actually a bit worse, and less detailed, than with XT32). The sub plot on the 'after' also looks like I've got some low bass issues, as well as around the crossover points I've tried (80-120 Hz).
What would be some recommended strategies?
- Try raising the surrounds even higher - or would that make the problem worse?
- Turn down the ST fronts and the CS8080 center to reduce excess bass
- Take more measurements in a broader area of the room to see if it smooths out some of the dips and humps
I have no wriggle room to move the center speakers, but a little room to adjust the surrounds in the back of the room, and can move the ST fronts in or out a few inches. Right now, the ST are flanking the entertainment center (maybe 1 ft. from a wall) at the front of our living room, the center is below our TV on a stand placed within our entertainment center, and I can move the surrounds maybe 6 to 8 inches away from their current positions, which about that distance from our back walls. I also know that ideally I should do a sub crawl, but I can't really move the subs to the sides of the room without moving a piano against the left side wall of our room. From their current position, if move our subs further out, it causes some aesthetic issues and WAF issues, since we'd have the left sub blocking the walk into the living room from our hallway.
Sorry for all the detail, but I thought it might be helpful to give the experts on the forum some idea of what I'm facing. Any advice would be welcome. Also, if the info I've given is too superficial, what else might be useful to get proper recommendations.