Sundown Audio SD-4 12" D2 Neo Shallow Mount Subwoofer | 600W RMS

The Sundown Audio SD-4 12" D2 Neo Shallow Mount Subwoofer is part of Sundown’s latest SD v.4 Neo Series, engineered for maximum performance in tight spaces. As the successor to the SD-3, the SD-4 series delivers world-class sound quality, improved cooling, and enhanced mechanical durability, all while maintaining a shallow mounting depth perfect for modern sealed-box applications.

Optimized for Shallow Mount Applications

The SD-4 series was designed specifically for enclosures with depth restrictions. Unlike traditional subwoofers, the SD-4 eliminates the need for pole vent clearance, allowing the motor to mount flush against the enclosure’s back wall. Combined with Sundown’s “W” shaped foam surround that reduces front clearance needs, this subwoofer has an effective total depth requirement nearly 2 inches less than most shallow subs of similar size.

Advanced Cooling & Motor Technology

• Neo Motor Design – Lightweight neodymium motor reduces angled depth requirements compared to the SD-3.

• Side-Firing Gap Venting & OD Pole Channels – Provides efficient airflow for superior cooling, even without a rear pole vent.

• Large Aluminum Faraday Ring – Smooths the acoustic response while lowering distortion.

• Shorting Ring – Minimizes inductance variation and distortion across the frequency range.

Precision Engineering for Sound Quality

The SD-4 uses an under-hung motor topology with a 1” thick top plate and a ½” long 8-layer copper voice coil. This design maintains constant winding within the magnetic gap, ensuring a flat BL curve and ultra-low distortion. With 14.5mm of linear excursion one-way, the SD-4 offers powerful, accurate bass that stays clean even at high volumes.

Built Tough for Daily Use & Competition

• High-Strength Cast Aluminum Frame – Patented design for rigidity and heat dissipation.

• 2.5" Black Aluminum Voice Coil Former – Provides excellent thermal handling.

• Stitched-On Tinsel Leads – Ensures reliability under extreme excursion.

• Spring-Loaded Terminals – Easy and secure wiring connections.

• Mechanical Ruggedness – Newly tooled spider and foam “W” surround provide progressive stiffness to prevent over-excursion damage.

Technical Specifications

• RMS Power Handling: 600W RMS

• Voice Coil Configuration: Dual 2 Ohm (D2)

• Xmax: 14.5mm one-way (by 70% BL)

• Voice Coil: 2.5” high-temp, 8-layer copper winding

• Surround: Computer-optimized foam “W” surround

• Motor: Lightweight neodymium with advanced cooling design

• Enclosure Recommendation: Optimized for small sealed boxes

• Frame: High-strength cast aluminum

Why Choose the Sundown Audio SD-4 12" D2?

The Sundown Audio SD-4 12" D2 Neo Shallow Mount Subwoofer is the perfect choice for enthusiasts who want deep, accurate bass in tight spaces without sacrificing durability or power. With its shallow mounting depth, advanced Neo motor technology, and rugged construction, the SD-4 delivers the performance Sundown Audio is famous for — now in a shallow-mount design built for today’s vehicles.

now Whether you’re building a sound quality system or need serious low-end in a space-limited install, the SD-4 is engineered to exceed expectations.