Memphis PRX12FT 12" Selectable-Impedance Subwoofer

The Memphis PRX12FT is a 12-inch Power Reference component subwoofer designed for adding controlled low-frequency output to a custom vehicle audio system. It handles 400 watts RMS and 800 watts peak, making it suitable for an amplifier-matched bass upgrade. Its selectable impedance design helps simplify system planning when amplifier requirements or future expansion needs may change.

This subwoofer uses Memphis FLEX Triple Selectable Impedance technology to present a 1-ohm, 2-ohm, or 4-ohm load through a repositionable jumper plug. That flexibility lets an installer match the woofer to a compatible mono amplifier without replacing the subwoofer. The same 400-watt RMS and 800-watt peak handling applies across the selectable impedance settings.

The PRX12FT is intended for listeners who want substantial bass from a single 12-inch driver while retaining options for system changes later. Its sensitivity varies slightly by selected load, rated at 85.6 dB at 1 ohm, 85.5 dB at 2 ohms, and 86 dB at 4 ohms. A properly selected enclosure and amplifier are important for getting the intended performance from the subwoofer.

Memphis uses Direct Voice Coil Cooling technology to help manage heat at the voice coil during operation. The design also incorporates a reinforced spider, improved suspension and coil design, and woven tinsel leads. These construction details support controlled cone movement and dependable signal transfer in a high-output car audio installation.

A black-on-black polypropylene cone and stitched butyl rubber surround give the PRX12FT a durable, understated appearance. With a 5.5-inch mounting depth and 11-inch cutout requirement, it can be used in many custom or prefab 12-inch enclosures with sufficient clearance. It supports sealed and vented enclosure approaches, allowing installers to prioritize compactness and control or greater output efficiency.

Key Features

• FLEX Triple Impedance: Select 1-ohm, 2-ohm, or 4-ohm operation with the included jumper.
• 400W RMS Handling: Matches with a properly configured amplifier delivering up to 400 watts RMS.
• Direct Voice Coil Cooling: Helps manage voice-coil heat during sustained playback.
• Polypropylene Cone: Provides a durable cone material for automotive bass applications.
• Stitched Butyl Surround: Supports cone travel with a durable rubber surround.
• 2-Inch Voice Coil: Uses a high-temperature TIL voice coil former.

Design & Installation

The PRX12FT combines a black polypropylene cone, stitched butyl rubber surround, reinforced spider, woven tinsel leads, and a high-temperature TIL voice coil former. Its 59-ounce magnet structure is fitted with a removable rubber magnet boot, while the steel basket provides a rigid mounting platform. Memphis also specifies improved suspension and coil design to support the driver’s bass-focused role.

Plan for an 11-inch cutout and at least 5.5 inches of mounting depth, plus sufficient rear clearance inside the enclosure. Select the impedance by moving the included FLEX Plug Jumper to the 1-ohm, 2-ohm, or 4-ohm terminal before connecting a compatible amplifier; the factory setting is 4 ohms. Memphis enclosure recommendations include sealed volumes from 1.0 to 1.5 cubic feet and vented alignments from 1.8 to 2.65 cubic feet, depending on the preferred bass character.