Hertz Mille Pro MPS 300 S4 Sub 12 Inch 30cm Shallow Car Subwoofer 4 Ohm 500w RMS

The Hertz Mille Pro MPS 300 S4 is a 12 inch (300 mm) shallow car subwoofer from Hertz's Mille Pro range, rated at 500W RMS (1000W peak) with a single 4 ohm voice coil and a mounting depth of just 88 mm.

This listing is the 4 ohm (S4) version. The MPS 300 is also available in 2 ohm (S2). A robust screw-less mesh grille is included.

Key specifications

• Size: 12 inch (300 mm) shallow subwoofer
• Power handling: 500W RMS, 1000W peak
• Impedance: 4 ohm single voice coil
• Mounting depth: 88 mm (3.46 in)
• Enclosure: sealed, from 22.7 L (0.8 cu ft)
• Frequency response: 25 – 400 Hz
• Voice coil: 38 mm six-layer copper
• Xmech: 20 mm
• Frame: die-cast aluminium, grille included

Extreme dynamics, unlimited power handling, realistic sound stage

Mille Pro Shallow Subwoofer key features:

• Ultra-shallow overall depth of 88 mm
• 500W continuous power handling
• Optimised for extremely compact sealed enclosures from 22.7 L (0.8 cu ft)
• Air Intercooling Revolution (A.I.R.) prevents air-compression-related limitations
• High mechanical excursion (Xmech 20 mm)
• Six-layer copper voice coil (38 mm / 1.5 in) for high thermal capacity
• Non-vented rear design allows reduced enclosure depth
• Robust screw-less mesh grille included with black screws provided
• Die-cast aluminium frame
• Solid horizontal 8AWG spring-loaded terminals
• EID: Scan, Discover, Identify

The MPS 300 S4 is designed for installs where space is severely limited — a typical example being a subwoofer enclosure fitted under the rear bench of a pick-up truck, where both space and height are restricted.

Despite its shallow profile, the MPS 300 S4 combines low mounting depth with high cone excursion (Xmech 20 mm). This is achieved through a dedicated support structure for the spider and coil that moves the magnetic group inwards, reducing depth whilst maximising linear cone excursion.