18" Subwoofers

Category Guide & Buying Information Fitment, power & selection tips

Shop 18-inch car audio subwoofers for high-output street, demo and competition systems. Compare RMS power, impedance, voice-coil configuration, mounting dimensions and model-specific enclosure requirements before selecting the woofer and amplifier.

Plan an 18-Inch Subwoofer Installation

  • Enclosure space: Verify the recommended net airspace, port requirements or sealed volume for the exact subwoofer before designing the box.
  • Mounting clearance: Check cutout diameter, motor clearance, mounting depth and the vehicle opening used to load the enclosure.
  • Amplifier load: Match rated amplifier output to the woofer's RMS rating at the final wired impedance.
  • Vehicle electrical: Size power and ground wiring, circuit protection, alternator output and battery support around the complete amplifier demand.

Match Every Part of the Bass System

An 18-inch cone does not define the enclosure or power requirement by itself. Use the manufacturer's specifications for the exact model and plan the woofer, enclosure, amplifier and electrical system together. Crystal Audio Solutions can help check the full combination before ordering.

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