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Amazon.com: Gemini Sound ZRX-S18P 18" Inch Woofer Professional DJ PA Systems Active Powered Subwoofers with 1600W Watts Class D Digital Power, 3" Voice Coil, Line/Link in XLR Connectors : Musical Instruments
Amazon.com: Eminence Professional Series Delta Pro-18A 18" Pro Audio Subwoofer Speaker, 500 Watts at 8 Ohms : Musical Instruments
Amazon.com: Sound Town 18” 1000W Cast Aluminum Frame Woofer (Low Frequency Driver), Replacement Woofer for PA/DJ Subwoofer Cabinets (STLF-18500A) : Musical Instruments
Amazon.com: Gemini Sound ZRX-S18P 18" Inch Woofer Professional DJ PA Systems Active Powered Subwoofers with 1600W Watts Class D Digital Power, 3" Voice Coil, Line/Link in XLR Connectors : Musical Instruments