Hertz MPS 250 S4 – 10" Shallow Subwoofer (4-Ohm)
$629.00 AUD
SKU: MPS250S4
Skip to product information
| Size | 10" |
| Power | 500W RMS |
| Year Range | 1998-2013, 2014-2023, 2024+ |
Hertz MPS 250 S4 – Ultra-Shallow 10″ 4-Ohm Subwoofer for Harley Touring
The Hertz MPS 250 S4 is a premium ultra-shallow 10″ subwoofer engineered for riders who want powerful, controlled bass without sacrificing all their storage space. With a mounting depth of only 82.6 mm and a 4-ohm voice coil, it fits where traditional subs cannot, making it ideal for Tour-Paks, saddlebag drop-in subs, and compact sealed Harley subwoofer enclosures.
Who This Is For
- Riders adding bass to a Harley-Davidson Touring bike where a conventional subwoofer will not physically fit.
- Tour-Pak, saddlebag drop-in or custom sealed pod builds working within tight depth and volume limits.
- Systems running a compact monoblock amplifier, since this is a 4-ohm single voice coil driver.
- Needs a sealed enclosure of 12–14 litres and at least 300 W RMS – the driver alone is not a finished build.
- High-output sub systems may require upgraded charging or a secondary battery, so budget for that if needed.
Key Features
- Ultra-shallow 82.6 mm mounting depth for maximum fitment flexibility.
- 4-ohm single voice coil ideal for moderate-power monoblock amps.
- 500 W RMS / 1000 W peak power handling for high-output motorcycle systems.
- Sealed-box optimisation delivers strong bass in genuinely compact enclosures.
- 16.8 mm Xmax and 20 mm Xmech enable deep bass even in small volumes.
- Die-cast aluminium basket resists vibration and flex in harsh riding conditions.
Why It Works on Harleys
- Perfect for tight spaces: Tour-Paks, saddlebag pods, side compartments.
- Considerably easier to package than a conventional subwoofer: 82.6 mm mounting depth against 115 mm for the CS 250 S4, and roughly 14 litres of sealed volume against 16 litres. Note that Hertz's tech sheet drawing gives a larger dimension for the CS 250 S4, so installers should confirm the figure before committing to a tight build.
- 4-ohm design pairs well with compact monoblock amplifiers.
- Strong low-end extension supports fairing and rear speakers without muddying vocals.
Recommended Power & Setup
- Amplifier Power: 400–600 W RMS ideal
- Minimum: 300 W RMS
- Enclosure Type: Sealed
- Sealed Volume: 12–14 litres (0.42–0.49 cu ft). Hertz's published reference enclosure is sealed 14.2 litres (0.5 cu ft) with a system resonance (Fc) of 49 Hz and Qtc 0.81.
- Low-Pass Filter: 80–120 Hz @ 12–24 dB/octave
- Electrical Note: High-output sub systems may require upgraded charging or a secondary battery.
Fitment
- Designed for Harley-Davidson® Touring motorcycles
- Ideal for Tour-Pak subwoofer boxes
- Compatible with many shallow saddlebag drop-in sub solutions
- Suitable for custom sealed pods built for tight space constraints
Specifications
| Subwoofer Size | 254 mm (10″) |
|---|---|
| Impedance | 4 Ω (Single Voice Coil) |
| RMS Power | 500 W |
| Peak Power | 1000 W |
| Sensitivity | 83.5 dB SPL |
| Xmax | 16.8 mm |
| Mechanical Excursion (Xmech) | 20 mm (0.79″) |
| Mounting Depth | 82.6 mm (3.25") |
| Overall Height | 103.2 mm (4.06") |
| Cone Material | Polypropylene |
| Recommended Sealed Volume | 12–14 litres, Hertz reference enclosure 14.2 litres at Fc 49 Hz and Qtc 0.81 |
| Weight | 5.1 kg (11.27 lbs) |
| Grilles Included | Yes – Hertz lists a screw-less mesh grille with black screws in the feature list. Please confirm pack contents with MAA if in doubt. |
| Resonant Frequency (Fs) | 29 Hz |
| Re | 3.3 Ω |
| Le | 3.65 mH |
| Vas | 21.2 L |
| Mms | 234 g |
| Cms | 0.11 mm/N |
| BL | 17.3 T·m |
| Qts | 0.48 |
| Qes | 0.52 |
| Qms | 5.6 |
Specifications per Hertz published technical documentation.
Need Box Design Advice?
Shallow subs demand precise enclosure volumes for the best performance. We can help you choose or design the ideal Tour-Pak or saddlebag enclosure to get the most from the MPS 250 S4.
Australia Shipping:
- Under $500 → $19.95
- $500–$2,500 → $14.95
- $2,500 and above → FREE
- Bulky items → +$25 surcharge (waived once your order reaches $2,500)
Fast dispatch from Brisbane. In-stock orders placed before 1pm AEST usually ship the same business day.
Change of mind: Request a return within 30 days of delivery. The product must be unused, unopened and in its original sealed packaging, valued at $50 or more, and you'll need an RMA number from us before sending anything. Return freight is yours, and a restocking fee of up to 15% may apply – we'll confirm any fee before the return is accepted.
Not returnable for change of mind: opened, installed or test-fitted items, special-order and custom products, custom harnesses, completed tuning, gift cards and items under $50.
Fitment: If we confirmed fitment in writing based on accurate bike details and it doesn't fit, we'll put it right and cover reasonable freight. Not sure? Ask us before you order – we're happy to help.
Faulty, damaged or wrong item: Contact us first with your order number. Faults follow our RMA and warranty process, and none of this affects your rights under the Australian Consumer Law.