Acoustic treatment steps for my HT room-Acoustics Forum-Acoustic Fields Forum

Hi,

I signed up to the forums to hopefully get some good advice to get me started with the acoustics in my HT/Mancave.
Overall I’m pretty happy with how my room sounds currently and Dirac does an excellent job of it, but I feel there is much more to be gained.
Especially the GIANT peaks I am experiencing with Dirac turned OFF (27Hz and 44Hz).

The room is in a basement, fully bricked, concrete/tiled floor, drywall ceiling against brick.
There is no real treatment in place besides the fluffy carpet and sofa.

My gear consist of this:
Arcam AVR550
MK Sound 750 LCR
MK Sound S150T surrounds
MK Sound SUR55T for Atmos
MK Sound V12 subs (2x)

In this Imgur link there are some pictures of the room;

Room 22 Jan 2020

Thanks!