The Electro-Voice EVID C10.1 loudspeaker system is a complete low frequency ceiling subwoofer package. The EVID C10.1 is designed to augment the low frequency response of any EVID ceiling speaker. The package consists of a bezel assembly grille rear enclosure 10-inch loudspeaker and internal linematching transformer. The EVID C10.1 loudspeaker utilizes a 2nd order crossover network to provide the correct band-pass frequency response for use with any EVID Ceiling loud speaker.