The SP series are high efficiency sound projectors designed to provide good speech intelligibility and background music in a wide variation of applications. They are all weather-proof treated to be used indoor as well as outdoor and are perfect suited to be used in large 100V broadcast systems such as train stations or airports. They all meet the IP56 Ingress Protection standard. The SP22 is a professional humidity and weatherproof unidirectional sound projector with a high efficiency level. It features a 5″ full range driver and a built-in 100V line transformer with power taps for 20 Watt, 10 Watt or 5 Watt, which can be selected by connecting the corresponding pair of the 4 core connection cable.