Spend the money on improving your listening environment if you really want to (it's a free world), but real 20Hz with decay for ambience is going to be extremely difficult with the dimensions of your room. And why? Most music has little to no first order 20Hz cycles. Are your trying for "Dafos", organ music, HT action movies? There's so much good music out there without 20Hz and trying to keep this particular parameter is going to be a money sink where you'll just piss it down a hole.
I've done it; Double Entecs, Maggie IV Bass Panels, Pow Wow. I never got it right to my ear and even turned those subs off during all my regular listening. Honestly, IMHO a well balanced music system with 20Hz bass is not in the cards for $20K.
I've done it; Double Entecs, Maggie IV Bass Panels, Pow Wow. I never got it right to my ear and even turned those subs off during all my regular listening. Honestly, IMHO a well balanced music system with 20Hz bass is not in the cards for $20K.