Atlas 15" room response

Ive got my atlas 15 in a 6.5 cu ft box tuned to 20hz via two 4" ports, and was curious what kind of frequency response i was getting, so i downloaded room EQ wizard and made some plots!

Here is the uncorrected results taken with a rat shack spl meter.

Would you guys reccomend i get a bfd? from what i can see my response is pretty good, in fact once you add in the correction values, it should be even BETTER.

After this plot it made me realise i was missing out on a fair amount of low end, must be the subsonic filter on the amp. Is anyone knowledgeable in lowering this down to say, 16hz? i still get enough output at 10hz to visibly flex my windows, so i would definately benefit from changing out the subsonic filter, after all, its free low end

just for people wondering my LxWxH of my room is 12x10x8
After looking at those correction values i have a MUCH better room response than i thought. Im not too concerned about that 19hz null because infasound linearity isnt too important. I think ill just keep it where it is and go eqless.

However i would still like to be able to lower that subsonic filter so its [email protected]

my predictions of room gain from the win isd graph were surprisingly accurate if not a little conservative.i guees i really am getting 6db/oct gain under 70hz