Hertz MPS 250 S4 Mille Pro Shallow 10 Inch Subwoofer 500W RMS

The Hertz MPS 250 S4 is a Mille Pro Shallow 10 inch (250 mm) shallow-mount car audio subwoofer with a single 4-ohm voice coil, rated 500 watts RMS and 1000 watts peak, with a mounting depth of just 82.6 mm (3.25 in.) for ultra-compact sealed enclosures starting at 14.2 liters (0.5 cu ft). It is a universal 12-volt component subwoofer built for installs where space and height are limited — the classic example is a box under the rear bench of a pickup truck.

Hertz reaches that depth without the usual shallow-sub excursion penalty: a dedicated support structure for the spider and voice coil lets the magnetic group move inward, cutting depth while delivering cone excursion Hertz rates 20 percent higher than a traditional shallow design (16.8 mm Xmax). The 38 mm 6-layer voice coil uses cooling openings on the former for thermal stability, the cone is polypropylene, and spring-loaded terminals accept up to 8 AWG cable.

What's Included

Sold as a single subwoofer. The robust screw-less mesh grille is included in the box.

Specifications

• Size: 250 mm (10 in.) shallow-mount component subwoofer
• Mounting depth: 82.6 mm (3.25 in.)
• Impedance: 4 ohm single voice coil (SVC)
• Power handling: 500 W continuous (RMS), 1000 W peak
• Frequency response: 25 - 400 Hz; sensitivity: 83.5 dB SPL
• Voice coil: 38 mm (1.5 in.) 6-layer with vented former
• Xmax: 16.8 mm; Xmech: 20 mm (0.79 in.)
• Cone: polypropylene; magnet: high-density flux ferrite, 134 x 55 x 36 mm
• Recommended enclosures: sealed from 14.2 l (0.5 cu ft, Fc 49 Hz); reflex 19 l (0.7 cu ft)
• Terminals: spring-loaded, accepting up to 8 AWG cable
• Grille: screw-less mesh grille included

Fitment / Compatibility

This is a universal 12-volt shallow-mount subwoofer with no vehicle-specific fitment — it installs in any car, truck, or powersports vehicle that can fit a slim 10 inch enclosure with 82.6 mm (3.25 in.) of mounting depth, such as under-seat or behind-seat boxes in pickup trucks. It requires an enclosure and an external amplifier. If you have full depth available, the standard Mille Pro MP 250 D2.3 (160 mm deep) offers higher power handling.

What size box does the Hertz MPS 250 S4 need?

Hertz optimized it for ultra-compact sealed enclosures starting at 14.2 liters (0.5 cu ft), and also publishes a 19 liter (0.7 cu ft) reflex recommendation.

Is the MPS 250 S4 a 2-ohm or 4-ohm subwoofer?

It is a single 4-ohm voice coil subwoofer, so it presents a fixed 4-ohm load — pair it with an amplifier rated for its 500 watt RMS handling at 4 ohms.

How shallow is the MPS 250 S4?

Its mounting depth is 82.6 mm (3.25 in.), roughly half the 160 mm depth of the standard Mille Pro MP 250 D2.3, which is what makes under-bench pickup enclosures possible.

Do I need an amplifier for the MPS 250 S4?

Yes. It is a passive component subwoofer with no built-in amplifier, so it needs an external amplifier driving its 4-ohm coil, sized against the 500 watt RMS rating.