Rockford Fosgate R2D4-12 12" Dual 4-Ohm Subwoofer

The Rockford Fosgate R2D4-12 is a 12-inch dual voice coil car subwoofer designed to add controlled low-frequency output to an aftermarket audio system. Its dual 4-ohm voice coils provide wiring flexibility when matching a compatible mono or multi-channel amplifier. This model is intended for custom sealed or ported subwoofer enclosures rather than direct factory-speaker replacement.

Rated for 250 watts RMS and 500 watts peak, the R2D4-12 is suited to systems built around moderate-power bass amplification. It is a practical choice for listeners who want fuller impact from kick drums, bass guitar, and electronic low end without selecting a high-power competition-oriented driver. Amplifier output should be matched to the RMS rating and final wired impedance.

The mica-injected polypropylene cone is paired with a high-density poly-foam surround to support consistent cone movement. A poly-cotton spider and high-temperature copper voice coil with aluminum former are used in the moving assembly. Together, these components are designed for everyday bass reproduction in a properly configured enclosure.

Rockford Fosgate uses optimized motor magnetics, an extended pole piece, and a bumped vented backplate in this model. These details support voice-coil ventilation and excursion control during operation. Flexible stitched-on lead wires and multi-point neck-joint bonding further support the driver’s mechanical construction.

The R2D4-12 can be used in either a sealed enclosure for a more compact installation or a ported enclosure for lower modeled bass extension. Its recommended sealed and ported box alignments provide a starting point for a system-specific build. With its dual 4-ohm coil configuration, it can be incorporated into single-subwoofer or multi-subwoofer systems with appropriate impedance planning.

Key Features

• Dual 4-Ohm Voice Coils: Supports flexible series or parallel wiring options.
• 250-Watt RMS Rating: Matches moderate-power subwoofer amplification.
• 12-Inch Subwoofer: Adds low-frequency output to aftermarket car audio systems.
• Polypropylene Cone: Provides a durable, lightweight moving surface.
• Vented Motor Design: Supports thermal management around the voice coil.
• Sealed or Ported Use: Works with two manufacturer-recommended enclosure alignments.

Design & Installation

The R2D4-12 uses an injection-molded polypropylene cone, sealed half-roll poly-foam surround, tear- and fatigue-resistant poly-cotton spider, and heavy-gauge stamped-steel frame. Its high-temperature copper voice coil uses an aluminum former, while all-metal compression terminals provide the amplifier connection point. A removable semi-flexible PVC motor cover is also part of the design.

Allow for a 5.067-inch mounting depth and an 11.25-inch mounting cutout diameter when planning the enclosure baffle. Rockford Fosgate lists a 1.02-cubic-foot sealed enclosure or a 1.79-cubic-foot ported enclosure tuned to 45 Hz as recommended starting points. Wire both voice coils correctly and use an amplifier whose stable load rating matches the final impedance configuration.