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The Ground Zero GZTF 4.0X is a 4″ (100 mm) 2-way coaxial car speaker rated at 70W RMS / 100W max, from the Ground Zero GZTF range. It features a structured HQPP cone, 13 mm Mylar tweeter, and a high-efficiency 3-ohm design for compact 10 cm mounting positions.
This listing is the GZTF 4.0X 4″. The GZTF range is also available in GZTF 5.2X 5″, GZTF 6.5X 6.5″, and GZTF 69X 6×9″.
Key specifications
- Size: 100 mm / 4″
- Power handling: 70W RMS, 100W max
- Impedance: 3 ohm
- Sensitivity: 90 dB
- Frequency response: 70 Hz – 22 kHz
- Tweeter: 13 mm / 0.51″ Mylar
- Mounting diameter: 93 mm / 3.66″
- Mounting depth: 51 mm / 2.01″
100 mm / 4″ 2-way coaxial speaker system
A compact 4″ coaxial upgrade built around a structured HQPP cone and 3-ohm impedance, delivering 70W RMS from a tight fit.
Features
- 2-way coaxial speaker system
- HQPP cone with 3D structure
- Rubber surround
- Resonance-free steel basket
- High-efficiency 3-ohm design
- 13 mm / 0.51″ Mylar tweeter
- Ferrite motor
- 6 dB/oct high-pass filter
- Includes protection grille
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Specification
| Model | 2-way coaxial speakers |
|---|---|
| Diameter | 100 mm / 3.94″ |
| Power handling | (RMS/max.) 70 / 100 Watts |
| Impedance | 3 ohms |
| Efficiency | 90 dB |
| Frequency Response | 70 Hz – 22 kHz |
| Tweeter | 13 mm / 0.51″ Mylar tweeter |
| Cone | HQPP cone with 3D structure |
| Mounting Ø | 93 mm / 3.66″ |
| Mounting depth | 51 mm / 2.01″ |
What's Included
- GZTF 4.0X
Ground Zero
About the Ground Zero GZTF 4.0X
From our tech experts at CEN
The Ground Zero GZTF 4.0X is a 4 inch (100 mm) 2-way coaxial car speaker rated at 70W RMS and 100W max. It uses a structured HQPP cone, a 13 mm Mylar tweeter, and a 3-ohm design suited to compact 10 cm mounting positions. A protection grille is included in the box.
Who it suits
The GZTF 4.0X suits drivers replacing worn factory speakers in smaller door or dash cut-outs. The 3-ohm impedance works with most standard head units without an external amplifier. Drivers with very limited mounting depth may want to consider the shallow-mount Ground Zero Iridium GZIF 4001FX instead.
Our tech experts advise
Confirm your mounting cut-out is at least 93 mm in diameter and that you have 51 mm of depth available before ordering. The 3-ohm impedance is compatible with most aftermarket and factory head units. Adding a small amplifier will make better use of the 70W RMS rating. Installation is priced per vehicle; visit our car audio installation page for details.
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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 Titanium
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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 deep is the GZTF 4.0X?
A: It needs 51 mm of mounting depth and a 93 mm mounting diameter.
Q: Will the GZTF 4.0X run from my head unit?
A: Yes. Its high-efficiency 3 ohm design and 90 dB sensitivity help it get more from a head unit. An amplifier lets it use its full 70W RMS rating.
Q: Is a grille included with the GZTF 4.0X?
A: Yes, a protection grille is included.
Q: Can CEN fit these speakers for me?
A: Yes. CEN offers professional installation from our Nottingham premises. Contact us to book an installation slot or ask for a fitting quote.
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