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Product details

Key Features
  • Silk dome tweeter helps deliver a smoother, more refined top end than harsher entry-level designs
  • Cast basket midwoofer gives the system a stronger foundation for control and stability
  • Component format allows better staging and imaging than a typical coaxial upgrade
  • Variable crossover adds useful flexibility during installation and tuning
  • Designed to offer a more musical, more resolved result than basic factory replacement speakers
Advanced Specifications
  • Product type: 2-way component speaker system
  • Series: Hydrogen Series
  • Model: GZHC 165.2
  • Diameter: 165 mm / 6.5″
  • Power handling: 130W RMS / 220W max
  • Impedance: 4 ohms
  • Efficiency: 88 dB
  • Frequency response: 40 Hz – 24 kHz
  • Midwoofer: GZHK 165
  • Tweeter: GZHT 25S
  • Tweeter outer diameter: 54 mm / 2.13″
  • Tweeter mounting cutout: 48 mm / 1.89″
  • Tweeter mounting depth: 22 mm / 0.87″
  • Cone: Non-pressed paper
  • Surround: Rubber
  • Basket: GZ aluminum cast basket
  • Voice coil: 38 mm / 1.5″
  • Motor: Ferrite
  • Crossover: Variable 2-way, 12 dB/oct
  • Tweeter cut-off frequency: 4500 Hz
  • Midwoofer mounting cutout: 144 mm / 5.67″
  • Midwoofer mounting depth: 69 mm / 2.72″
  • Grille: GZ hexagon style protection grille included
  • Verification: Verified with KLIPPEL®
Best Suited For
  • Front stage upgrades in daily driver systems
  • Users wanting a more refined and musical result than entry-level speakers
  • Systems using amplifier power or higher-quality source components
  • Installations where tweeter placement can be optimised for better staging
  • Buyers looking for a quality 6.5 inch component set without moving into very high-end pricing
Why OSCA Backs This Product

This is the kind of speaker set that makes sense when you want a genuine step up from basic replacement speakers without chasing something overly aggressive or difficult to live with. It has the right sort of ingredients for a more resolved, more enjoyable front stage.

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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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