2 Units Sometimes you need all the bottom-end you can get. That's where the Mackie SWA1501 Active Subwoofer System comes in. The SWA1501 features an internal 500-Watt Mackie FR (Fast Recovery) Series amplifier and a high-precision 15" transducer, custom designed for optimal performance with the amp
TRUE ACTIVE SUBWOOFER
Active doesn't just mean the SWA1501 has an amplifier bolted on its back—it means optimized electronics that provide complete control and maximum performance over all components. The onboard Active system controls the crossover filters, equalization, protection for the transducer and electronics, and provides real time vigilance over the entire system. There is simply no way that you can get this kind of full system functionality by strapping an amp on the back of a passive speaker box.
