Welcome!
Suggest starting out by reading Floyd Toole's "Sound Reproduction" 3rd edition. It is the consummate audiophile guide to learning how loudspeakers and subwoofers behave in-room. Toole is perhaps the most respected acoustician for home/studio. The book will direct you to buy loudspeakers with good spinorama (special anechoic chamber testing) and trained double blind comparative listening results (unfortunately highly rare). Next, develop a well shaped (not small) and effectively insulated room. Third use multiple carefully place subwoofers to reduce inherent in-room bass peaks/dips this step will save you from buying full range speakers). Then treat as needed with absorbent bass traps (suggest going to GIK here at Audio Circle). Finally tweak with room correction EQ.
I've done all this. My 8ft x 13ft x 21ft room is 15 years old, well insulated (don't forget the door and ductwork), use three subwoofers, ten GIK 2ft x 4ft 244 absorbent panels, and Dirac room correction. My mistake was using recessed light fixtures and the builder not installing a suspended drywall ceiling (noise transmits up and down, but not normally a problem). I also beefed up the electrical while at it with dedicated 20 amp circuits, one per each of three cryo'd hospital grade receptacles that are grounded together apart from the rest of the house. Have heard power aberrations (the technical term for dirty power) but never at home in lower central Michigan.
