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Product details

Key Features
  • Compact 6.5 inch format makes real bass possible in extremely limited spaces
  • Long-stroke design gives the driver far more low-frequency capability than a typical small woofer
  • Dual 2 ohm configuration gives useful flexibility for compact mono amplifier setups
  • Reinforced paper cone and copper voice coil support proper subwoofer duty, not just midbass use
  • Can work in very small vented enclosures while still delivering meaningful output
Advanced Specifications
  • Product type: High-quality SPL subwoofer
  • Series: Radioactive Series
  • Model: GZRW 6XSPL
  • Diameter: 16.5 cm / 6.50″
  • Power handling: 350W RMS / 700W max
  • Impedance: 2 x 2 ohms
  • Efficiency: 79 dB
  • Power recommendation: 250 – 700W
  • Voice coil: 50 mm / 2″ copper
  • Cone: Reinforced paper
  • Surround: Long stroke compound surround
  • Basket: Resonance-free steel
  • Spider: Polycot
  • Dust cap: IMPP with 3D structure logo
  • Xmax: 22 mm / 0.866″
  • Mounting diameter: 147 mm / 5.79″
  • Mounting depth: 99 mm / 3.90″
  • Resonance frequency (Fs): 49.5 Hz
  • Qts: 0.621
  • Vas: 2.2 L / 0.078 cu.ft.
  • Verification: Klippel® optimized
Enclosure Recommendation
  • Vented enclosure: 20L net / 0.71 cu.ft.
  • Port: 1 x 7 cm / 2.75"
  • Port length: 17.72"
  • F3: 28 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
  • Ultra-compact substage builds
  • Motorcycles, small vehicles, and tight custom installs
  • Systems where enclosure space is extremely limited
  • Users wanting real subwoofer performance from a very small driver
  • Installations where a conventional 10 or 12 inch sub is not practical
Why OSCA Backs This Product

The big appeal here is that it can deliver real low-end output without needing much space. That is what makes it interesting, because most drivers this size are a compromise first and a subwoofer second.

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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