If you are looking for a portable powerful wireless sound system, the Sound Machine is one of the best of its class. A 10" Eminence woofer and 1" titanium compression driver provides clear sound - ideal for both speech and music. This is one of our top selling systems popular among marching band directors, auctioneers, fire/rescue squads, outdoor event planners, and other professions requiring volume and clear speech to reach large crowds. On an open UHF channel, we have used the transmitters up to 300 feet away from the base receiver. Made in the USA.