JBL Club 1024 10" component subwoofer with switchable 2- or 4-ohm impedance at Crutchfield
JBL LSR310S 10" Powered Studio Subwoofer (Each) | Guitar Center
Amazon.com: JBL Club WS1000 10" Shallow Mount subwoofer w/SSI (Selectable Smart Impedance) Switch from 2 to 4 ohm Bundled with Alphasonik Earbuds : Electronics
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