4) refers to some subwoofer present while in the system. This type of setup will have a focused speaker created to drive out the bass notes, Which’s completed Together with the subwoofer. It's usually squat and boxy, and it is created to be positioned at ground level, where by the https://angelojjjgf.thezenweb.com/not-known-details-about-best-sound-system-for-home-theater-71040854