What process did you use to integrate multiple subwoofers for 2 channel listening?

Hilde45 - lots of great information here and ways to do this. I have four large subwoofers and measured the room (speakers and listening position) with Room EQ Wizard and then input that data into Multi Sub Optimizer via an Earthworks M30 microphone to generate filters everything running out of my Mini DSP with balanced connections which is processing all filters at 56bit/ 96kHz. The results are stunning and perfect integration. 
Thanks,
Steve

Thanks, Steve. That sounds like a great result!

@hilde45 -

Duke LeJeune (AudioKinesis) wrote:
So imo you are definitely playing the distrubuted multisub game already! If you can elevate one of the subs so that it is closer to the ceiling than to the floor, you get bonus points. This is one of the things that @hleeid did to get good results in his 11 x 13 foot room; I think he actually elevated three of the four Swarm subs, as that was more practical than the other way around in his room.

So yes.  That is true.  The room was actually a bit smaller due to closets. 
Had a conversation with Duke about this. 

Even Duke had reservations about the extremely small room.  But I mentioned to him a thread he posted about elevating one or more subs above the room mid height which would contribute to dispersion in the vertical plane.

The light bulb went off in my head.  After some measurements, I figured a way to make 4 subwoofer easily fit by elevating three of them.
One was mounted on the wall behind me above my head.
The one sub on the floor also served as a lamp table next to my desk.

NOTE:  The only limited floor space sacrificed was for the ''lamp table'' sub.

NOTE 2: I must respectfully disagree with Duke about my good results.
They were not really good.

Shockingly incredible would better describe the experience!  Even before hooking up the 4th sub, let alone elevating some of them.

In my new place, I have my mains (Harbeth SHL5+ 40s) firing diagonally across my 13' x 16' (9' ceiling) office.
Two subs are ceiling facing.  One at 12'' and the other 18'' from the ceiling.
Each of these are near the corners along the long wall.
One sub on the floor is slightly behind and to the right of the right speaker.
The other floor sub is to forward and to the right of my desk (my listening position).

After much experimentation with speaker/listener position, light acoustic treatment, etc. I feel this is my best (currently) sounding setup all around.
No DSP, EQ, etc.  except for reversing phase on the sub closest to the mains and unporting the sub furthest from the listening position.

Best of luck to you on your quest!

@hleeid Thanks for your post. I tried some elevation but didn't help. Turned out that a different bit of advice from Duke was key -- partly plugging the ports on my stand mount speakers.

I'm happy to report that I now have no more than +/- 6 db peaks or nulls on my system and much less than that in the bass regions, most of the time. The combination of 3 sub placements, room treatments, and port plugging has dialed the room in to what I think are the best limits for this space. 6.5' ceilings made this a major project, but I have learned a lot. The bass is very accurate and full now.

No worries!
Great to hear of your progress!
You are in for a delight!
Enjoy!