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

See my posts on bass and room treatment. A huge amount of boomy bass was eliminated with vibration control- Townshend Podiums and Pods- and a lot of the rest went away with F1 cables. Yes wire contributes to resonance problems.   

If I had gone the traditional tube traps first approach I would now be struggling to restore that which was being unnecessarily removed with expensive bulky tube traps. 

It's a new millennium, boys. One sub is out, DBA is in. Panels are passe, HFT are hot. Podiums trump traps. Etc, etc.

@hilde45 wrote: "...the orange "morning" line is speakers only.  Improvement from "Morning scan, without subs" to "Afternoon scan, with subs" mitigates the dip significantly at various points, e.g. pulling up a null by 10 db at 129 hz, by 8 db at 241hz."   

Maybe I'm just slow, but eyeballing the curves I would have thought that Orange was WITH subs, and Green was speakers ONLY.   

Anyway assuming that's the only difference, AND that the microphone locations and other measurement conditions are identical, the curves imply that the subs are active pretty high up.  Where are you rolling off the top end of the subs?  

Incidentally the dip around 270 Hz and peak around 540 Hz look to me like floor bounce artifacts (perhaps modified by the ceiling bounce) and imo should NOT be EQ'd away.  

Duke

Been testing all day, off the computer. I've definitely improved things a lot with systematic adding in of each sub and then doubling the amount of treatment at ceiling first reflection points. I'm now dialing in a variety of room treatments. Be back when I can.

+1 on ceiling treatments, often overlooked.

MiniDSP 2 x 4 HD, a calibrated mic ( Umik-1 or Dayton ), a db measurement tool of your choice ( decibel: db sound level app on iPhone is great ), REW app on your laptop, YouTube tutorial Episode 7 from "Hometheatergurus" channel ( along with the gain matching episode )  and you will get absolutely amazing results if your willing to go through the headaches of a learning curve. 
I have a Focal 1000F, Def Tech SC4000 and an old Def Tech SC-1
 ( how's that for a crazy ridiculous mix?!! ) and it literally sounds like I have a single subwoofer from the main listening position. The SC4000 is only about 5-6 feet behind the listening position so occasionally ( but rarely ) I have to adjust the volume but it has remote control and through my Harmony hub it's easy as pie to do.
  MiniDSP allows for 4 configurations ( again controlled through the Harmony hub ) that I have set from flat response to a couple of different mid bump options to play with depending on the movie or music track and my listening whim at the moment. 
  A long time issue I've dealt with from just one to two to three sub configuration is now a mute point. Although nothing is perfect, the technology available is a wonderful tool if your willing to give it a try. I guarantee it's better than any " by ear " method, I don't care how good your ear is or how long you crawl around your room. Your just finding bumps in frequency at different areas of your room and not flat response anyway . There are too many factors so let technology be your friend. You ( and your ears ) will be glad you did.

P.S. - room treatments would be a great addition to the equation. That will
         be my next step hopefully.