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Amazon.com: Klipsch R-12SW Powerful Deep Bass Front Firing 12" Copper-Spun Driver 400W Digital Power Subwoofer 14" X 18.5" X 16" : Electronics
Amazon.com: Klipsch R-100SW 10" Subwoofer, Incredibly Deep Bass and an All-digital Amplifier,14 5" x 12 5" x 16 4" : Electronics
Amazon.com: Alpine R2-W12D4 Next Gen 12" Sub R-Series Dual 4-Ohm Voice Coils 2250 Watts Peak Subwoofer Includes HA-A800.1 Mono Amplifier : Electronics