Audison AVBX 12 D4 II 12" Sealed Subwoofer Box

The Audison AVBX 12 D4 II is a loaded 12-inch passive subwoofer enclosure designed for vehicle systems that need substantial low-frequency support without requiring a deep enclosure. Its sealed, ultra-shallow format helps it fit more easily in space-conscious trunk and cargo-area installations. It is built around the matching Audison AV 12 D4 II dual-voice-coil subwoofer.

This enclosure is suited to listeners building an OEM-upgrade or custom car-audio system who want controlled bass from a ready-to-install box. The sealed alignment is engineered for defined bass notes and natural decay rather than the character of a ported enclosure. Its 25-400 Hz rated frequency response supports integration with a properly configured front speaker system.

The installed AV 12 D4 II driver uses dual 4-ohm voice coils, providing flexibility when planning amplifier load and wiring configuration. It is rated for 550 watts continuous power handling and 1100 watts peak power handling. A 84.5 dB sensitivity rating and 16.8 mm Xmax support meaningful low-frequency output when paired with a suitable amplifier.

Audison uses a high-density 15 mm MDF enclosure with internal bracing to help control panel vibration and enclosure resonance. The loaded driver combines an aluminum chassis, high-density-flux ferrite magnet, CCAW voice coil, glass-fiber former, and polypropylene cone with mica injection. These materials are selected to support rigidity, excursion control, and dependable thermal behavior.

The AVBX 12 D4 II is part of Audison's VOCE II system family and can serve as the bass foundation of a component-speaker upgrade. Its 2S² architecture supports either down-firing or up-firing placement according to available vehicle space and acoustic goals. The integrated Sub Smart Plug terminal provides both plug-and-play and push-connector connection options for system integration and service access.

Key Features

• Loaded 12-Inch Enclosure: Includes the AV 12 D4 II subwoofer in a purpose-matched sealed box.
• Dual 4-Ohm Voice Coils: Provides wiring flexibility when matching a compatible subwoofer amplifier.
• 550W Continuous Handling: Supports substantial amplifier power with appropriate setup and gain adjustment.
• Ultra-Shallow Sealed Design: Helps preserve cargo space while supporting controlled bass response.
• 15 mm Braced MDF Cabinet: Adds enclosure rigidity and helps reduce unwanted panel resonance.
• 2S² Orientation Architecture: Allows down-firing or up-firing placement to suit the installation.

Design & Installation

The AVBX 12 D4 II uses a sealed enclosure constructed from high-density 15 mm MDF with internal bracing. Its driver features an aluminum chassis, high-density-flux ferrite magnet, CCAW voice coil, glass-fiber former, polypropylene-with-mica cone, and rubber surround. The enclosure measures 607 mm by 401 mm by 175 mm across dimensions A, B, and C in Audison's dimensional drawing.

This is a passive subwoofer box, so it requires a separate compatible amplifier, wiring, and signal integration in the vehicle. Use the dual 4-ohm voice-coil configuration only with an amplifier that is stable at the resulting wired load, and set crossover and gain controls correctly for the system. Measure the intended mounting area before purchase, then choose down-firing or up-firing orientation based on clearance and the desired installation layout.