Rockford Fosgate P3SD4-8 8" Shallow DVC Subwoofer

The Rockford Fosgate P3SD4-8 is an 8-inch shallow-mount car subwoofer designed for installations where conventional subwoofer depth is unavailable. Its compact motor and 2.66-inch mounting depth help it fit in space-limited vehicle locations while adding dedicated low-frequency output. Dual 4-ohm voice coils provide useful wiring flexibility when matching an amplifier.

This model is intended for listeners building a compact bass system, replacing a factory subwoofer, or adding low end to a vehicle with limited enclosure depth. It is rated for 150 watts RMS and 300 watts maximum power handling. The 38-250 Hz frequency response supports subwoofer duty when used with an appropriate low-pass crossover.

The P3SD4-8 uses an anodized aluminum cone and dustcap with an M-Roll Santoprene surround. These materials are paired with a dual linear spider and embedded tinsel leads to support controlled cone movement. Its 82 dB sensitivity and shallow design make it a practical option for compact, amplifier-driven systems.

Rockford Fosgate equips this shallow P3S model with a StampCast basket and integrated spider venting. The venting design is intended to help manage motor temperature during operation. A shallow motor assembly helps maintain the low mounting-depth requirement without changing the subwoofer's 8-inch fitment format.

The P3SD4-8 can be used in either sealed or vented enclosures. Rockford Fosgate specifies a 0.25 cubic-foot sealed enclosure or a 0.75 cubic-foot vented enclosure for this driver. Its dual 4-ohm coils can be wired in series or parallel to create an 8-ohm or 2-ohm final load for a compatible amplifier.

Key Features

• Shallow-Mount Design: A 2.66-inch mounting depth supports installations with limited clearance.
• Dual 4-Ohm Voice Coils: Allows 2-ohm or 8-ohm wiring configurations for one subwoofer.
• 150W RMS Handling: Matches well with an amplifier rated around its continuous power capability.
• Anodized Aluminum Cone: Provides a rigid cone material for bass reproduction.
• Integrated Spider Venting: Helps the motor manage heat during operation.
• Sealed Or Vented Use: Supports compact sealed or larger vented enclosure designs.

Design & Installation

The P3SD4-8 combines an anodized aluminum cone and dustcap, M-Roll Santoprene surround, dual linear spider, aluminum voice-coil former, and hybrid StampCast basket. It includes a diamond-cut cast-aluminum trim ring, while a grille is optional rather than included. The driver uses dual 10 AWG compression-style speaker terminals.

Confirm a 7.13-inch cutout and at least 2.66 inches of mounting clearance before installation. Use a properly built sealed 0.25 cubic-foot enclosure or vented 0.75 cubic-foot enclosure, and wire both voice coils for an amplifier-stable final impedance. For subwoofer operation, an active low-pass crossover in the 80-100 Hz range is recommended in the owner's manual.