Hertz MP 250 D2.3 10" Dual 2-Ohm Subwoofer

The Hertz MP 250 D2.3 is a 10-inch Mille Pro Series component subwoofer designed for custom car-audio enclosures. Its dual 2-ohm voice coils provide wiring flexibility for compatible mono or multi-channel amplification. It is intended for listeners building a system that needs substantial low-frequency output without moving to a larger woofer.

Rated for 600 watts continuous power and 1,200 watts peak power, this subwoofer is suited to an appropriately matched external amplifier. The dual 2-ohm configuration can be wired to a 1-ohm parallel load or a 4-ohm series load with one subwoofer. Proper amplifier load capability, gain setting, enclosure construction, and crossover setup remain important to system performance.

The pressed-pulp cone incorporates mineral powders to combine rigidity with damping. Hertz uses an exponential V-cone profile intended to help the cone maintain controlled piston-like behavior through its operating range. A Boundary Free IIR rubber surround increases available radiating area while retaining a compact nominal frame diameter.

The MP 250 D2.3 uses a 65 mm, four-layer CCAW voice coil and a high-density ferrite motor. Its TIL-P voice-coil former includes venting behind the winding to support heat dissipation. The published electro-acoustic specifications include a 30 Hz resonant frequency, 83.5 dB sensitivity, and ±17 mm Xmax.

This driver can be used in a manufacturer-specified 17 L sealed enclosure or a 22 L reflex enclosure. A sealed setup is the more compact option, while the reflex design follows Hertz's specified tuning and port dimensions. It is a component subwoofer, so an enclosure, amplifier, wiring, and installation hardware should be planned as part of the complete system.

Key Features

• 600 W Continuous Power: Supports use with a suitably matched external amplifier.
• Dual 2-Ohm Voice Coils: Allows 1-ohm parallel or 4-ohm series wiring for one driver.
• Mineral-Injected Pulp Cone: Combines a pressed-pulp diaphragm with mineral powders for rigidity and damping.
• Boundary Free Surround: IIR rubber surround increases usable emission area within the nominal frame size.
• 65 mm CCAW Voice Coil: Four-layer coil construction is designed for the published power rating.
• Six-Spoke Alloy Basket: Aluminum alloy basket provides a rigid, vented mounting structure.

Design & Installation

The MP 250 D2.3 is built around a high-density flux ferrite magnet, pressed-pulp mineral cone, and Boundary Free IIR rubber surround. Its six-spoke aluminum alloy basket includes venting beneath the spider, while the basket edge has a CNC-machined diamond-cut finish. The terminal block accepts up to 8 AWG speaker cable and includes a protective plastic cover.

Allow for a 236 mm (9.29 in.) mounting cutout and 141 mm (5.55 in.) mounting depth when designing an enclosure. Hertz specifies a 17 L (0.60 cu. ft.) sealed enclosure or a 22 L (0.78 cu. ft.) reflex enclosure, each using 19 mm (0.75 in.) wood in its published examples. For one subwoofer, wire the coils in parallel only with an amplifier rated for a 1-ohm load, or wire them in series for a 4-ohm load.