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Product details

Key Features
  • Massive 70 mm Xmax gives it the excursion to produce serious low-frequency output
  • 3 inch CCA voice coil is built to handle real amplifier power
  • Heavy-duty cast basket keeps the structure stable under extreme load
  • 4-layer Nomex spider supports control and durability at high excursion
  • Dual 2 ohm configuration gives flexible amplifier matching for high-power systems
Advanced Specifications
  • Product type: High-performance SPL subwoofer
  • Model: GZNW 30SPL-D2
  • Diameter: 30 cm / 12″
  • Power handling: 3000W RMS / 6000W max
  • Impedance: 2 x 2 ohms
  • Efficiency: 86.3 dB
  • Power recommendation: 2000 – 6000W
  • Voice coil: 75 mm / 3″ CCA round wire
  • Cone: Reinforced paper
  • Basket: Solid aluminum cast
  • Spider: 4-layer Nomex
  • Dust cap: Carbon design
  • Xmax: 70 mm / 2.76″
  • Mounting diameter: 281 mm / 11.06″
  • Mounting depth: 237 mm / 9.33″
  • Resonance frequency (Fs): 41.3 Hz
  • Qts: 0.54
  • Vas: 25 L / 0.88 cu.ft.
  • Verification: Klippel® optimized
Enclosure Recommendation
  • Vented enclosure: 60L net / 2.12 cu.ft.
  • Port (dimensions): 10 cm / 4"
  • Port length: 4.13"
  • Fb / F3 (-3 dB): 47 Hz / 37 Hz

* Above-mentioned enclosure recommendations are just a few possible variations. Please note that you should find the perfect tuning, especially port length, based on your car and own taste.

Best Suited For
  • High-output daily systems using serious mono amplification
  • SPL-focused builds wanting a hard-hitting 12 inch substage
  • Systems chasing strong bass authority without moving to a larger 15
  • Large enclosure builds designed around output and impact
  • Installations with the electrical support to run real power properly
Why OSCA Backs This Product

What stands out here is the combination of 70 mm Xmax and the 3 inch CCA voice coil. That gives the sub both the excursion to move serious air and the thermal capacity to handle real power, which is exactly what makes a high-output 12 actually feel convincing in the car.

Trusted Brands for Serious Systems

Selected for Real-World Performance

Cutting Through the Noise of Car Audio

About Ground Zero 🚀

Ground Zero, established in 1995, is a German-engineered car audio brand with strong American performance roots, known for delivering high-output, competition-proven equipment built on real engineering, not hype. With distribution in over 80 countries and a full range of system components developed in Germany, the brand has earned global respect through consistent results in independent testing and demanding installs. From its origins in high-excursion subwoofer design to its evolution into a complete system solution, Ground Zero remains a go-to for enthusiasts and installers who value output, reliability, and proven performance.

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