2 subs in a small room?


I recently added a REL T/5i sub to my system and have been very happy with the results.  Integration was a breeze and I am now more engaged in my music than ever.  So of course being a typical audiophile, I got to thinking if 1 sub sounds this good will 2 sound even better?  The challenge is my room.  Its very small at 9' w x 10' l x 9' h.  The back wall is about 3' high, above which it opens up to the rest of my house.  I have bass traps in this room.  Right now, using just 1 sub, my freq response from 20-1000hz is +- 2db with a -4db dip at 200hz and a +4db hump at 40hz.  Not perfect but my system still sounds amazing.

I know the general consensus is a second sub will sound better but I am concerned with the size of my room.  Will adding a second sub in such a small space over power it or will it actually help to smooth out nodes?


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Tbooe 

If my understanding of Dirac is correct, it should be a breeze to integrate a pair of subs.  If you're not using it yet, you may find that your existing, single sub set-up sounds much improved.
I have a 13.5 X 13.5' listening room and decided to bring up my JL  Audio e110 sub from the basement HT system to hear what it sounded like. It helped greatly, so I bought a second sub and have no regrets. I do have DIY bass traps in all 4 corners now and the crossovers on the subs turned down, just filling in the bottom octave. The biggest impact in my system so far.
lancelock, may i ask where you placed the second sub relative to the first?  I understand the second one should not be placed in the same mirrored location.  
I recently went from a single to stereo pair of subs, wanted to move more air, what I was not prepared for was the startling effect on midrange to high frequencies! More detail, wider stage, no joke it was jaw dropping. The explanation I found was there is a phase shift from summing 2 channels into one sub, or mono, masking information, had I known this years ago would have done a pair right from the start I second meerzistar's advice!   

perfectpathtech, may I ask where you placed the second sub relative to the first? I  know each room is different but I am just trying to get a feel for sub placement.