Purpose-engineered and built for real marine duty, MX-Series coaxial systems deliver excellent performance at a more affordable price than our maximum-performance M-Series models. The oversized 7.7-inch design of the MX770-CCX results in increased efficiency (more output for a given amount of power). This gives them the ability to play louder and cleaner at high volumes than smaller speakers. The woofer design is optimized to operate with a large volume of air behind it (at least 2 cu. ft. / 57 l). Operating this coaxial system in less space will compromise its low frequency performance. A 0.75-inch pure silk dome tweeter, specially treated to withstand the marine environment, handles the high-frequency duties. Silk has been chosen for its lightness, excellent damping properties and smooth response