Amazon.com: DC Audio LVL3-M2 12" Level 3 900W/1800W Dual-2-Ohm Car Audio Subwoofer/Sub : Electronics
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Amazon.com: XO Vision Pre-Amp Subwoofer Level Controller to Attenuate Any Line Level Signal : Musical Instruments
Boss Bx45 2/3-way Electronic Crossover Remote Subwoofer Level Control (2 Pack) : Target
DC Audio M2 Level 4 12 Inch Subwoofer - Specification and Price – Droppin HZ Car Audio
Kenwood P-XRW1202WB 12" Subwoofer in a Sealed Wedge Enclosure with a X502-1 eXcelon Series 1000W Max Power Class D Mono Amplifier with a KCA-RC01A Wired Remote Level Control - Creative Audio
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