I have plenty of clear bass from my 2 way speakers 7 inches driver.that i listen to with my stomach......
It was not so, only few months ago....
The secret : is not passive treatment of the room with inert materials ONLY and MAINLY....
My secret is active devices controls of the room with a balance between, absorption, reflections, and diffusions, and using device (different diffusors of my creation and active resonators connected to a grid of low cost Schumann generators) to take the positive side of reverberations for example....
But i will not speak about that because of dogmatism by some and sheep thinking, and i dont want to be ridiculed...I look already nuts enough for my taste.... :)
I am in listenings experiments for the last 2 years and i totally transform my system less with ideas from a book, than from experiments....
You are right this subject is too hot and complex to touch it, especially if someone is unorthodox and try anything that will work for his ears....You will go otherwise against patented specialist and crowds ....
Anyway any acoustical treatment and controls are TOTALLY individualized by the content and geometry and topology of the room....They are standardized only for make easy the job of selling materials....
What we can do with a small room is not the same we can do with a big hall or even with a big room....
Going on only with equations in some computer will not have make my room what it is now at peanuts costs.... Then trust yourselves, and your ears, be creative, dont give any money and listen .... It is fun and miraculous....
Some will say that our ears are biased, but it is ridiculous argument anyway, who lives in my room ? My biased ears live here.... Not a deaf computerized sellers....
By the way we need to treat a room not for bass, but for all frequencies to work giving natural timbre first.....
And the effect of a good acoustical controls of the room will be spectacular in nearfield listening AT THE SAME LEVEL, in a different way for sure, but at the same level of improvement that in regular position contrary to what some are saying.....
My best....