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4 Inch 4 Ohm 100w Subwoofer Speaker | 8 Inch Subwoofer Speaker 6 Ohms - 1pcs 4 Inch - Aliexpress
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Wiring subwoofers — what's all this about ohms?
Hypnotic HWP8 SUBWOOFER 8" 4 OHM DVC 500 watts Rms 1000 max DB Research 811536033567 | eBay
Subwoofer wiring diagrams
Amazon.com: Massive Audio SUMMOXL124-12 Inch Car Audio Subwoofer, High Performance Subwoofer for Cars, Trucks, Jeeps - 12" Subwoofer 1500 Watt RMS, 3000w MAX Dual 4 Ohm, 3 Inch Voice Coil. Sold Individually : Electronics