Robust, stable, and flexible with a commanding sonic presence, QSC E Series passive speakers and subwoofers are just the thing for venue installations centered around live band performances, DJ and dance shows, karaoke, theater, and other events. QSC E Series Speakers are further enhanced when you combine them with a QSC Power Amp or TouchMix digital mixer, allowing you to tap into the powerful on-board DSP (digital signal processing) controls and expertly crafted audio presets. The E Series includes 10-inch (E110), 12-inch (E112), 15-inch (E115), and dual 15-inch (E215) speaker models, as well as 18-inch (E118SW) and dual 18-inch (E218SW) subwoofers - that means you can build up a powerful system and either add more speakers or swap them out as the situation dictates.