Originally Posted by JimP
After rereading your last few post, I also think that you're seated in a null.
If you are up to it, you need to get one of the frequency analysis programs such as REW so that you can tell what's really going on. Or better yet, post over on home theater shack where you live and if someone would come by to check it for you.
My best guess without any testing is that the sub would do best along the side wall 1/3rd the room dept. Then rerun Audyssey with it in that position using multiple sweeps without moving the mic. Find your preferred spot and leave the mic there.
Another way to run the crawl test is to put the sub in your primary listening position and walk around the room till you find the spot that it sounds the best. This doesn't mean, the loudest but rather evenly distributed frequencies in the subwoofer range. Don't forget to turn audyssey off before you do this test. Then after you find the best spot for the sub, rerun Audyssey.
Also, if you're lacking the 50-80hz midrange, buying another sub to fill this area is likely to be a problem intergrating and then you're confined to very nearfield placement. Which then creates problems with timing. If its farfield placed, then the null would likely take over and kill those frequencies again. The Ultra when properly intergrates has good midbass. If you tend to sit nearer the sidewall, that's contributing to your problem. (I do the same) Sit more towards the lateral middle of the room and see if that helps.
Best of luck and let us know how it sounds.
I did the sub crawl by placing the sub in my seat, I even put it on the couch. I usually sit in the right side of the couch, against the wall, near the QS8. It definately works best being in the back half of the room, right now it's about halfway between the A/V equipment, and the loveseat, against the wall, firing down the room towards the screen. I am totally open to changing my seating position if I have to. Perhaps I should try the placing the sub in a few different locations and walk around the room to see which place has the best overall bass content, rather than just the highest output. I thought that was pretty much what I had done but now I am second guessing.
I actually had the sub about 1/3 of the way up to begin with, to the left of the loveseat (you can see it in the first picture). I put it there for looks because honestly I figured this sub would be plenty and placement wouldn't be as important, which I am finding is truly not the case at all. It needs to be set about 10 db higher there to get the same output, which is fine, but that kind of goes against the whole sub crawl thing. Someone linked me to some files you can burn to a cd that will play every hz from 10 - 100 and then you can plot the levels to see the peaks and lows, I think I will do that tonight.
Trust me, I do not want to buy another sub if I don't have to. It just blows when you spend 300+ hours working, and a lot of money on something, and just this one area is disappointing, the rest I am thrilled with.
I think what I will do is try running the CD and plotting the results. If there are significant dips where I sit, I'll try it again after doing a new sub crawl with a different seating location.