The Posh CIW 6.5 Chambered In-Wall Speaker is a cost-effective way to gain exceptional sound quality in a controlled acoustic environment. Utilizing a 6.5" coaxial driver with a 3/4" hard-dome tweeter and a computer-designed porting system, the CIW6.5 delivers impressive bass response and well-defined high frequencies. The coaxial design makes this speaker ideal for either in-wall or in-ceiling applications, maintaining consistent sound quality no matter how large the dead space in the wall or ceiling.The injection-molded polystyrene acoustic chamber provides consistent predictable performance in all applications by controlling the air space behind the wall. This creates an effective vapor barrier and controls 2nd and 3rd order harmonics, virtually eliminating standing waves inside the wall.