The Best High-Performance Subwoofer | Reviews by Wirecutter
Amazon.com: Massive Audio GTX64 – 6.5 Inch Car Audio Subwoofer, High Performance Subwoofer for Cars, Trucks, Jeeps - 6.5" Subwoofer 250 Watt RMS, 500w MAX Dual 4 Ohm, 1.5 Inch Voice Coil. Sold Individually : Electronics
Amazon.com: Cadence 8 Inch Car Subwoofer, High Performance 800 Watts Dual 2 Ohm 2 Inch Black Aluminium 4 Layer Voice Coil, Ultra Shock Series Car Audio Woofer US8D2, Single : Electronics