ConcertaConcerta On-wall loudspeakers are engineered to perform on walls, not just hang on them. Concerta on-wall speakers have been shown to deliver remarkably flat frequency response across an exceptionally wide listening area for clean, accurate sound in real-world listening rooms. None of the competing systems tested under identical conditions performed as well.The Revel B1 is a high-performance powered subwoofer, designed to add essential bass response to any music or home theater system. The B1 subwoofer delivers accurate and authoritative bass from a surprisingly compact enclosure. Adjustable controls, parametric room equalization and multiple connection options provide unequalled placement flexibility and allow you to optimize low-frequency performance for any listening environment.Woofer composed of micro ceramic composite (MCC) allows for strength and stiffness but very little weight. Nomex/cotton blend spider for increased linearity. 2 (51mm)-diameter copper voice coil would on a Kapton bobbin for impressive power handling. Parametric room EQ functions Downward-firing port allows for placement against a wall or cabinet.