Hertz DS25-3 10" 4-Ohm Car Audio Subwoofer

The Hertz DS25-3 is a 10-inch, 4-ohm car audio subwoofer from the Dieci series designed to add dedicated low-frequency output to an aftermarket sound system. It is intended for listeners who want stronger bass response than factory full-range speakers can provide. Its 250 mm driver size makes it suitable for many compact subwoofer enclosure installations.

This subwoofer uses a polypropylene cone with mica injection and a high-excursion butyl rubber surround. The cone includes deep surface ribbing to increase rigidity, while the surround supports controlled driver movement. Together, these construction choices are designed for low-frequency reproduction in a car audio environment.

The DS25-3 is rated by Hertz for 150 watts continuous/program power handling and 600 watts peak power handling at 4 ohms. Its 89 dB sensitivity and 32-400 Hz frequency-response specification support use as a dedicated bass driver. A 38 mm copper voice coil on an aluminum former helps manage thermal and mechanical demands during operation.

A high-density ferrite magnet and venting system are used in the motor structure. The venting design is intended to improve heat dissipation and help maintain consistent performance. Hertz specifies 9 mm Xmax and 16 mm maximum mechanical excursion for the driver.

The DS25-3 is designed for compact sealed or reflex enclosure applications, making it a flexible option for a custom trunk, hatch, or cargo-area bass upgrade. Hertz publishes enclosure data for both 15.3-liter sealed and 18-liter reflex designs. Pair it with a compatible 4-ohm subwoofer amplifier and a properly designed enclosure for a complete low-frequency system.

Key Features

• 10-Inch Subwoofer: Adds dedicated bass capability to a car audio system.
• 4-Ohm Impedance: Works with amplifiers stable at a 4-ohm load.
• 150W Continuous/Program Rating: Supports appropriately matched external amplification.
• Mica-Injected Polypropylene Cone: Provides a rigid, purpose-built bass diaphragm.
• Butyl Rubber Surround: Supports high-excursion driver movement.
• Compact Enclosure Compatibility: Designed for sealed or reflex box applications.

Design & Installation

The DS25-3 combines a high-density flux ferrite magnet with a 38 mm pure-copper voice coil wound on an aluminum former. Its polypropylene cone is reinforced with mineral powder and uses deep ribbing for added rigidity. The butyl rubber surround and vented motor system complete a design focused on controlled excursion and heat management.

Plan the installation around the 234 mm mounting-hole diameter and 116 mm mounting depth, while allowing clearance for the rear magnet structure and wiring. Hertz provides sealed and reflex enclosure data, so the driver should be mounted in a properly built enclosure rather than used without one. An external amplifier, subwoofer wiring, enclosure, and installation hardware are required for operation; the optional Hertz DSG 250.3 grille can be added for driver protection.