Sub Set up Final Exam Question

I have a pair of Vienna Acoustic Beethovens in the Front, cables are only about 8-12 from source. My rear speakers are Vienna Haydn's. Those wires go around the side of my house in the rear (Home theatre set up), 30-45 feet. My subwoofer is the same, about 30 feet, same as the left rear. I have a new Titan Le I am breaking in. Everything works off my Denon 5803amp. I am hooking up the sub to my amp's, "Theatre Out" connection, on a single coax cable. Lastly, rather than placing the sub next to the mains, it is in the rear left (right if facing the rear wall) courner. Please help me with some ideas on Phasing. I am getting some weird overlapping bass.
Hi Maitrega. Can you describe the "overlapping bass"?

I can think of two possibilites. Either the crossover for the Titan is set too high, and therefore creating too much overlap with the mains, which in turn creates a hump at that frequency. Or the Titan is over-reinforcing certain frequencies because of it's close proximity to the rear corner.

Are your Beethovens set to "large" [full range] with a low crossover, and the Haydns on "small" with the sub? Or are the Beethovens set to "small" with a higher crossover point between them and the Titan?

Revel advises loading up their subs in corners. But they use an equalizer in conjunction with their crossover and amp to attenuate any humps caused by that placement. Subs that don't utilize an equalizer require more care with crossover selection and sub placement.

Make sure your crossover is set so that there is no frequency overlap. You might even want to try leaving a bit of a gap if the Denon allows. Once that is squared away, experiment with placement of the Titan. Try moving it away from the rear corner along the back wall or side wall and see what difference that makes. You'll probably lose some impact and "boom" when not in the corner, but you'll flatten the response and gain in areas of detail. Also play with the phase setting whether you choose the rear or side walls.

Good luck!
Yet another common situation! There's lot's of this sort of thing out there, with high end or otherwise! This is why, time and time again, I always try to recommend people to PLEASE ENLIST THE HELP OF QUALIFIED, EXPERIENCE, SKILLED PROFESSIONALS! If you're into making this your life long endevor, and have lots of time and desire on your hands, that's one thing. But most people sadely end up with less than stellar set up's, even with the best gear available! and others offer consulting for such room/set up/acoustical problems. YOu might consider consulting them.
Good luck
Asa with main speakers just putting time into placemtn can be very time comsuming (to the point of being maddening!) but can make more differnce than anything else in a system.One would obviously place the sub nest to the rear wall to re-inforce the amount of bass but how far into the corner and than setting the crossover point and volume can take a lot of time.But just like main speakers when you have it right I liken the effect to linning the two halves of the circles in a Camers's focus.It can with speaker placement dramatically snap into focus.Time and experimentation can really pay off.
I have 'The Force' by ACI. After the break-in period, I started serious tweaking. I crossed-over at 45 Hz with my full range speakers (80Hz would be correct if you are using the preamp internal crossover). I also took the sub out of the corner (where it was producing a very ugly boominess) and placed it slightly in front and outside the right speaker. The most important tweak was building a sandbox. My system has never sounded so good. Have fun!