The JBL's CONTROL CRV is a single compact loudspeaker that may be used indoors or outdoors. Dual 4" woofers are housed in a stylish, weather-resistant chassis to offer high-quality sound. This public address system is equipped with a 70/100V transformer and can be used with low-impedance systems. Because of the curved design, you may arrange speakers in half-round or complete 360° arc clusters.