Would adding a second subwoofer overpower my room?


I am considering adding a second subwoofer to my system.  The purpose of the second sub would be to eliminate nodes in the room and improve system focus.  My room is 14 feet by 16 feet.  I currently have one REL S5 sub positioned in a corner behind the left speaker.  The system consists of Wilson Sophia 3 speakers, a BAT Rex 80 watt stereo amp, an ARC REF 5SE pre amp and a BAT VTK12 phono stage.  I listen to 90% vinyl and an occasional CD through an Ayre CD player.  As my listening room is relatively small, would I over charge the room by adding a second sub.  The current sub is set to come in at approximately 28 cycles, which is below the bottom output of the Sophias.  Also, would other benefits be noticed by adding the second sub?   Thanks! 
ewah
The second sub is where the magic is. Takes some time with placement but it has the potential to improve everything, maybe dramatically.
Bass traps first, then EQ. :)

A dual sub would be even better, but start with that first, you may find you no longer care. :)

Best,

E
Thanks guys, very inciteful information.  I have an spl meter and will give the test tones a go!  Thanks,  ewah
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Nope, you will accomplish what you desired- to eliminate room nodes and improve focus.

B