Hertz MPS 250 S4 10-inch Peak 1000W  Car Subwoofer

When space is genuinely tight — we're talking under-seat, under-bench, or a boot build with almost no depth to spare — the Hertz MPS 250 S4 is one of the most capable options available. At just 82.6mm deep and happy in a sealed box as small as 14 litres, this 10-inch Mille Pro subwoofer delivers real bass performance in spaces where most drivers simply won't fit. If you've been told you can't have good bass because your car doesn't have the room, this is the sub that proves otherwise.

What is the Hertz MPS 250 S4?

The MPS 250 S4 is a 10-inch shallow-mount subwoofer from Hertz's Mille Pro series. It's built for installations where depth is the primary constraint — pickup truck under-bench enclosures, under-seat builds, and compact boot installs where a 12-inch or standard-depth sub simply won't fit. It handles 500W continuously and peaks at 1000W, runs at 4 Ohm with a single voice coil, and is optimised for ultra-compact sealed enclosures starting from just 14 litres (0.49 cubic feet). The driver uses Hertz's A.I.R. technology and a purpose-engineered suspension structure to deliver 20% more cone excursion than a conventional shallow-mount design, all within an 82.6mm overall depth.

Why Choose the Hertz MPS 250 S4?

• ✅ Ultra-shallow 82.6mm depth — one of the shallowest 10-inch subs available
• ✅ Works in sealed enclosures as small as 14 litres — genuinely compact box requirements
• ✅ 1000W peak power from a driver that's barely 3.25 inches deep
• ✅ A.I.R. technology prevents thermal compression during sustained high-power use
• ✅ 20% more mechanical excursion than traditional shallow designs
• ✅ Non-vented rear design allows even shallower enclosure builds
• ✅ Six-layer copper voice coil for high thermal capacity and long-term reliability
• ✅ Die-cast aluminum frame for rigidity under high-excursion loads
• ✅ Solid 8AWG spring-loaded terminals for a secure, rattle-free connection
• ✅ Screw-less mesh grille included for a clean, finished install
• ✅ 4 Ohm single voice coil — compatible with virtually any standard mono amplifier

Key Features

• Size – 250mm (10 inches): A compact driver diameter that enables under-seat and very shallow boot installations while still delivering genuine bass extension.
• Power Handling – 500W Continuous / 1000W Peak: Handles serious amplifier output without distortion or thermal failure, despite the compact form factor.
• Impedance – 4 Ohm, Single Voice Coil: Standard 4 Ohm load works with virtually any mono subwoofer amplifier on the market.
• Depth – 82.6mm (3.25 inches): Shallower than the 12-inch MPS 300 series, making it the right choice when depth is the absolute limiting factor.
• Optimised Enclosure Volume – 14L to 14L (0.49 CF): Works in genuinely tiny sealed boxes, enabling installs that no standard subwoofer could manage.
• Voice Coil – 38mm (1.5 in.) Six-Layer Copper: High thermal mass keeps the coil cool during extended high-power sessions.
• Xmech – 20mm (0.79 in.): 20% greater mechanical excursion than conventional shallow designs, delivering deeper bass from a smaller package.
• Non-Vented Rear Design: Eliminates rear ventilation clearance requirements, allowing the enclosure to be built right up to the back of the driver.
• 8AWG Spring-Loaded Terminals: Horizontal solid terminals accept thick gauge wire and hold it securely without loosening over time.
• Screw-less Mesh Grille: Included with black screws for a clean, professional finish.
• Die-Cast Aluminum Frame: Rigid basket construction resists flex at high excursion levels.
• Frequency Response – 25Hz to 400Hz: Full bass range from deep sub-bass to upper bass frequencies.
• Magnet – High Density Flux Ferrite: Powerful magnetic motor in a compact form factor.
• Cone – Polypropylene: Lightweight and stiff for accurate, responsive bass reproduction.

Advanced Technologies

A.I.R. – Air Intercooling Revolution: In a sealed enclosure, air compression during high-excursion movement generates heat that builds up in the voice coil and degrades performance over time. This is a particular challenge in very small enclosures like the 14-litre boxes the MPS 250 S4 is designed for. Hertz's A.I.R. technology manages this thermal environment directly, preventing the compression-related limitations that cause shallow subwoofers to lose output at sustained high volumes. The result is consistent, reliable performance even during long, demanding listening sessions in the tightest of enclosures.

Dedicated Suspension Support Structure: The MPS 250 S4 achieves its 82.6mm depth through a purpose-engineered suspension design. Hertz redesigned the spider and coil support structure with a dedicated support frame that allows the magnetic group to move inward, reducing overall depth while simultaneously increasing the linear excursion range. This is why the MPS 250 S4 achieves 20% more cone travel than a conventional shallow-mount design — it's a fundamental re-engineering of the driver architecture, not a trade-off.

Non-Vented Rear Design: Most subwoofers require clearance behind the magnet for ventilation. The MPS 250 S4's non-vented rear eliminates this requirement entirely, meaning the enclosure can be built right up to the back of the driver. In under-seat builds and pickup truck under-bench enclosures where every millimetre of depth matters, this makes a real practical difference to what's achievable.

EID – Scan, Discover, Identify: Hertz's EID system lets you scan the product to verify authenticity, access full specifications, and confirm compatibility. It's a quick way to check you have a genuine Hertz product and to pull up installation documentation on the spot.

Benefits

• 🔊 Genuine 10-inch bass performance from a driver just 82.6mm deep
• 📦 Fits in sealed boxes as small as 14 litres — the smallest enclosure requirement in the Mille Pro shallow range
• 🌡️ A.I.R. technology keeps performance consistent even in very small enclosures at high volumes
• ⚡ 4 Ohm single voice coil works with any standard mono amplifier
• 🔧 Non-vented rear means shallower enclosure builds are possible
• 🛡️ Die-cast aluminum frame handles high-excursion loads without flex
• 🔌 8AWG spring-loaded terminals make wiring clean and secure
• ✨ Mesh grille included for a finished, professional install appearance

Who Should Buy the Hertz MPS 250 S4?

• Car owners who want under-seat bass without any visible enclosure
• Pickup truck owners building under-bench enclosures with very limited height
• Hatchback and sedan owners with minimal boot depth available
• Installers building sealed enclosures in the 12–14 litre range
• Anyone running a standard 4 Ohm mono amplifier looking for a matched compact shallow sub
• Buyers who want Hertz Mille Pro quality in the most space-efficient package possible
• Anyone who has been told their car doesn't have room for a subwoofer

Technical Specifications

Why Choose Dolphin Accessories?

• ✅ 100% Genuine Products – Every product is sourced directly from authorised distributors. No counterfeits, no grey imports.
• ✅ Expert Guidance – Our team knows car audio. We'll help you match the right amplifier, enclosure, and wiring for your specific vehicle and setup.
• ✅ Pan-India Delivery – We ship to every corner of India with careful, secure packaging so your gear arrives in perfect condition.
• ✅ Secure Packaging – Premium products get premium protection. Every order is packed to handle the journey.
• ✅ After-Sales Support – Questions after your purchase? We're here for installation tips, compatibility queries, and troubleshooting.
• ✅ Trusted by Enthusiasts – Thousands of car audio lovers across India rely on Dolphin Accessories for their upgrades.

Frequently Asked Questions

Q: What makes the Hertz MPS 250 S4 different from the MPS 300 S4?
A: The MPS 250 S4 is a 10-inch driver versus the 12-inch MPS 300 S4. It's shallower at 82.6mm versus 88mm, and works in smaller enclosures from 14 litres versus 22.7 litres. Choose the 250 S4 when space is the absolute priority; choose the 300 S4 when you can accommodate a slightly larger box and want more low-frequency extension.

Q: What enclosure size does the MPS 250 S4 need?
A: It's optimised for ultra-compact sealed enclosures starting from 14 litres (0.49 cubic feet). This is one of the smallest enclosure requirements of any 10-inch subwoofer, making it ideal for under-seat and under-bench builds.

Q: Can I install the MPS 250 S4 under the seat?
A: Yes. At 82.6mm (3.25 inches) deep, it's one of the shallowest 10-inch subwoofers available. Whether it fits under your specific seat depends on the vehicle, but it's designed precisely for this type of installation.

Q: What amplifier power does the MPS 250 S4 need?
A: It handles 500W continuously at 4 Ohm. An amplifier rated between 250W and 500W RMS at 4 Ohm will drive it cleanly and reliably without risk of thermal damage.

Q: What is A.I.R. technology on the Hertz MPS 250 S4?
A: A.I.R. stands for Air Intercooling Revolution. It's a thermal management system that prevents heat buildup caused by air compression in sealed enclosures during high-power use. This is especially important in small 14-litre boxes where air compression is more pronounced.

Q: Is the MPS 250 S4 compatible with standard mono amplifiers?
A: Yes. The 4 Ohm single voice coil is the most common impedance for mono subwoofer amplifiers, so it will work with virtually any standard mono amp.

Q: What does the non-vented rear design mean?
A: It means the back of the driver doesn't require ventilation clearance. This allows the enclosure to be built right up to the rear of the magnet, enabling shallower overall box dimensions — critical for under-seat and under-bench builds.

Q: How does the MPS 250 S4 achieve 20% more excursion than traditional shallow designs?
A: Hertz redesigned the spider and coil support structure with a dedicated support frame that allows greater linear cone travel within the same shallow depth. This is what gives the MPS 250 S4 its depth-to-performance advantage over conventional shallow-mount drivers.

Q: What terminals does the MPS 250 S4 use?
A: It uses solid horizontal 8AWG spring-loaded terminals. These accept thick gauge wire and hold it securely, making for a clean, rattle-free connection.

Q: Does the Hertz MPS 250 S4 come with a grille?
A: Yes, a screw-less mesh grille is included along with black screws, giving the installation a clean, finished appearance.

Q: What is EID on Hertz products?
A: EID stands for Scan, Discover, Identify. It's Hertz's product authentication system — scan the EID code to verify the product is genuine and access its full specifications and documentation.

Q: Where can I buy the Hertz MPS 250 S4 in India?
A: You can buy it right here at Dolphin Accessories. We offer 100% genuine Hertz products with pan-India delivery, secure packaging, and dedicated after-sales support.