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The Ground Zero Iridium GZIW 165 is a 6.5″ (16.5 cm) 4 ohm car subwoofer rated at 100W RMS, part of Ground Zero's Iridium range. Klippel optimised for low distortion, it uses a 3D HQPP cone and long-stroke design for tight, accurate bass from a compact driver.
This listing is the 6.5″ GZIW 165. The Iridium subwoofer range is also available in the GZIW 250 10″ 250W RMS.
Key specifications
- Size: 6.5″ / 16.5 cm
- Power handling: 100W RMS
- Recommended amplifier power: 60–150W
- Impedance: 4 ohm
- Sensitivity: 85.5 dB
- Voice coil: 38 mm / 1.5″ copper
- Xmax: 10 mm / 0.39″
- Mounting diameter: 147 mm / 5.79″
- Vas: 9.1 L
16.5 cm / 6.5″ high quality subwoofer
A compact 6.5″ subwoofer built for tight, accurate bass. Klippel® optimised for low distortion, with a solid 3D HQPP cone and long-stroke design for clean output at 100W RMS into 4 ohm.
Features
- 6.5″ subwoofer
- Klippel® optimised
- 3D HQPP cone
- Long-stroke rubber surround
- Solid aluminium cast basket
- 38 mm / 1.5″ copper voice coil
- Polycot spider
- IMPP dust cap with 3D structure logo
Explore the full range in Ground Zero Iridium.
Specification
| Model | High-Quality subwoofer |
|---|---|
| Diameter | 16.5 cm / 6.50″ |
| Power Handling | (RMS) 100 Watts |
| Impedance | 4 Ohms |
| Efficiency | 85.5 dB |
| Power recommendation | 60 – 150 Watts |
| Voice coil | 38 mm / 1.5″ copper |
| Membrane | HQPP cone with 3D-structure |
| Max. Excursion (Xmax) | 10 mm / 0.39″ |
| Mounting Ø | 147 mm / 5.79″ |
| Resonance frequency (Fs) | 41 Hz |
| Overall quality (Qts) | 0.41 |
| Equiv. air volume (Vas) | 9.1 L / 0.32 cu.ft. |
What's Included
- GZIW 165
Ground Zero
About the Ground Zero GZIW 165
From our tech experts at CEN
A Ground Zero 6.5 inch subwoofer, 4 ohm, handling 100w RMS.
Who it suits
Drivers building a system where the bass keeps pace with the front stage, and competition builds where output is the point.
Our tech experts advise
Enclosure volume and tuning decide most of what you hear. We build enclosures to suit both driver and vehicle at our Beeston workshop. Installation is priced per vehicle, so get in touch with your make, model and year and we will confirm what it needs. See car audio installation.
Explore the full Ground Zero range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all Ground Zero
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Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
- 1
Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
- 3
Fitted at our workshop
Bring it to our Beeston workshop and we do the rest.
Unit 25 Technology Drive, Beeston, Nottingham NG9 1LA
More from Ground Zero Iridium
More options from the same range, in stock and ready to go
Frequently Asked Questions
Q: How do I choose the right amplifier for my speakers or subwoofer?
A: Match the amplifier's RMS output per channel to the RMS handling of your speakers or subwoofer at the same impedance. The Specification tab lists the power figures. If in doubt, contact CEN with your setup and we will recommend a match.
Q: How much amplifier power does the GZIW 165 need?
A: It is rated at 100W RMS, and Ground Zero recommends an amplifier delivering 60 to 150 watts into 4 ohms.
Q: What size mounting hole does the GZIW 165 need?
A: It needs a 147 mm mounting diameter.
Q: Can CEN fit this subwoofer for me?
A: Yes. CEN offers professional subwoofer and amplifier installation from our Nottingham premises. Contact us to book an installation slot or ask for a fitting quote.
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