Ah ok cool, so it's nothing to do with the character of the sound. I have a small room but I want the house and techno kicks and bass to hit you in the chest and rumble your throat like a high end club system like Funktion One. A physical experience. My room is: 153 ft2 / 1260 ft3. A lot of things are tricky to get in the UK but it's relatively easy to get SVS, Arendal. I could import RSL or JTR (fortune) but then I guess I have no customer support or warranty. Perlisten are available but are also a fortune. Someone recommended 2x REL HT/1510 Predator Subwoofers. I do like to have XLRs if possible.
I was analyzing what I listen too and yeah most of the hard hitting low end is at 40-50hz. There is bass down to 10hz but by the time it reaches 30hz it's dropped to -36db.
I have a small room but I'm considering large to extreme subs - I'm not sure if that's wise but I don't want to be lacking anything either. I want it to play up to100db long term (or however much is necessary)although most of my sensible listening is 85db to 90db. I need it to be flat for studio work and prefer no latency or unnoticeable latency.