low bass response

So...I miss read your room dimensions ! I'd sit 2/3 of the way back from the speakers and if that doesn't help then I'd add a JL f113v2. I did about three months ago along with their CR1 crossover. You can dial in the set up in very very fine and flexible increments. Additionally Roon's DSP EQ is excellent and very flexible. You can simply roll up the 3050 hz region a few db leaving everything else untouched and see if it helps. And- it's about $8k cheaper than the JL sub and CR1.

IMO it's your room size, not your furniture nor your amp/speakers. Bass frequencies are "long" and need physical distance to travel without piling up and stacking up in a room. Your room is too small for the speakers you have. Treating the room won't work I don't think- you need a larger space. I own the same amp btw and it produces plenty of bottom end and has driven Focal 1038BE, Focal Sopra 2, Harbeth 30.2, Harbeth HLS5 Super and is currently driving Wilson Sabrina in a 13 x 22 sonically "tight" dedicated listening room. I think you need a larger room, or smaller speakers and ideally you'd need to get further back from the speakers.