Oh !!! u sold it.Of course I don't want to divert this thread.Please share your experience on that in minidsp thread below,so that it may be useful for those who are in similar situation/requirement.
I'm starting a thread on minidsp . I'm an user of minidsp 2*4HD model .I have used it for alignment of multisubs for HT purpose.It offers great flexibility .It can be used for stereo purpose for better integration of subs to make it 2.1 or 2.2,but never tried it personally. I'm still a learner...
www.hifivision.com
I have seen in international forums ,people integrate 18" sub with a 12" sub too... even sealed and ported.Of coure it require more knowledge ,and one should know what they are doing...
Coming back to the thread , sub crawl may not work for 2 sub integration as the combined reponse of 2 subs will be different.
What I suggest OP is to gain match the subs first .
Since many don't have UMIK (if possible try to get it to run REW) .. Adjust the distance of subs individually ,one at a point and check the performance.Also if the sub has variable phase settings ,that too can be adjusted and tried.
Similarly try different possible placment of subs .