Memphis MJM812 8" MOJO Mini Selectable-Impedance Subwoofer

The Memphis MJM812 is an 8-inch MOJO Mini component subwoofer designed for vehicle audio systems that need substantial bass output without moving to a larger woofer size. Its compact format helps make it practical for custom enclosures and installations where available space is limited. The subwoofer is intended for use with an external amplifier and a properly designed enclosure.

Memphis FLEX selectable-impedance technology lets the MJM812 be configured for either a 1-ohm or 2-ohm load. This gives installers flexibility when matching the subwoofer to an amplifier's stable operating impedance. Included jumper wires are used to select the desired load.

With a 900-watt RMS and 1,800-watt peak power rating, the MJM812 is built for high-output bass systems using an appropriately matched amplifier. Its 8-inch cone format supports a focused low-frequency upgrade while requiring less enclosure space than many larger subwoofers. The selectable load keeps the same published power handling in either configuration.

The design combines a V-Groove rubber surround, reinforced spider, fiberglass-reinforced dust cap, and vented cast-aluminum basket. The folded surround is designed to increase excursion while preserving effective cone area. Direct Vent Voice Coil cooling and an aluminum heat sink help manage heat during sustained operation.

The MJM812 can be used in either sealed or ported enclosures, allowing the system to be tailored around available space and listening preferences. Memphis lists a 0.6-cubic-foot sealed enclosure and a 1.0-cubic-foot ported enclosure recommendation for one subwoofer. It is a suitable option for a dedicated compact bass upgrade or for multi-subwoofer systems built around compatible amplification.

Key Features

• FLEX Selectable Impedance: Choose a 1-ohm or 2-ohm load for amplifier matching.
• 900W RMS Handling: Supports high-power mono amplifier applications when properly configured.
• V-Groove Rubber Surround: Supports cone travel while maintaining usable cone area.
• Direct Vent Voice Coil Cooling: Helps dissipate heat from the voice-coil assembly.
• Cast Aluminum Basket: Provides a rigid, vented foundation for the moving assembly.
• Fiberglass-Reinforced Dust Cap: Adds stiffness to the cone assembly.

Design & Installation

The MJM812 uses a vented cast-aluminum basket, 105-ounce magnet structure, aluminum heat sink, reinforced spider, and double-stitched V-Groove rubber surround. Its 2-inch, 4-layer copper voice coil is paired with DVVC cooling to support thermal management. A removable rubber magnet boot is also fitted around the magnet structure.

Plan for a 7.32-inch cutout diameter and 5.75-inch mounting depth, while verifying clearance in the intended enclosure before cutting. Select the 1-ohm or 2-ohm configuration with the supplied jumper wires only after confirming the amplifier can safely operate at that load. For enclosure design, use the published sealed or ported volume guidance and set amplifier gain and crossover controls carefully to avoid distortion or overdriving the subwoofer.