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?


128x128tboooe
tbooe, sorry wife has that crappy flu been busy the last few days. 
In response to your first question, I am running mine 5' behind
my mains offset in the center.

As for the second question, my speakers are full range, I run the subs off a second set of outputs on my source, my amps and speakers are not connected in any way to the subs, except for ground at the source.  The improvement in the upper end is a
constant regardless of whats played.  


perfectpathtech8 posts04-26-2016 8:51am ...The improvement in the upper end is a 
constant regardless of whats played.  
Thank you for the reply and I hope the wife feels better.  
This last comment is what gets me so confused.  I get how a sub can help with smoothing out the sound when playing.  But in the absence of a xover or room correction, how can a sub help with other areas of the freq range when it is not outputting sound?  I am assuming of course that during a song, the sub is not always playing anything.  What am I missing here?
Thanks, she's been throwing up for almost 10 days, really nasty virus.

It is hard for me to wrap my mind around as well, as I understand it
summing 2 inputs L + R into mono creates as phase shift which translates into signal smear if you will, I assume because its low signal its a connection thing the smear happens at the inputs and has no bearing on wether the subs are playing or not. If I leave the subs off or on the improvement is there. Glad to hear you are going to add a second one this year, you will not regret it!    

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tboooe, I have a room that is 10' x 13' x 8'. I have two back ported LSA1 speakers on stands. I have both in corners and only about 6" from it. I have very good bass and wouldn't  think of adding a subwoofer. I have never had any success with even two of them.