Ground Zero
Ground Zero GZIF 40X 4″ 2-way coaxial speaker system
SKU: GZIF 40X
Ground Zero GZIF 40X 4″ 2-way coaxial speaker system
Closeout, remaining stock
Ground Zero GZIF 40X 4 Inch 2-Way Coaxial System
Polypropylene cone, mylar dome tweeter, 90dB sensitivity. Built to work on head unit power in the locations nothing bigger fits. Discontinued line, remaining stock only.
- Closeout
- Discontinued
- Final sale
What You Are Buying
A pair of 4 inch coaxials for dash pods, rear doors and the shallow factory locations that will not take a 5.25. Discontinued, and we are not restocking it.
Read this before you buy
Final sale. No returns, no exchanges, no manufacturer warranty. Discontinued model with no replacement pipeline.
The One Number That Matters Here
90dB sensitivity
On a 4 inch driver that is high, and it is the specification that decides what this speaker is for. Most 4 inch coaxials land in the low to mid 80s, where a factory head unit at 18 to 22W per channel produces a thin, quiet result. 90dB is roughly 6dB above that, which is four times the acoustic power from the same amplifier.
Practically: these will make a factory system sound like it got louder, not just clearer. That is unusual in this size and it is why the speaker exists.
What Ground Zero Published, and What They Did Not
What is documented
- 4 inch woofer with a polypropylene cone
- Mylar dome tweeter
- 90dB sensitivity
- Integrated crossover, no external components
- Universal fitment for standard 4 inch locations
What is not documented
- Power handling, RMS or peak
- Impedance
- Frequency response
- Mounting depth and cutout diameter
We are not going to estimate those. If depth or impedance decides the purchase, ask and we will measure a pair and read the packaging before it ships.
What the Materials Tell You
Polypropylene cone
Dimensionally stable, indifferent to humidity, and self-damping enough not to ring hard in the upper midrange. The default at this tier, and a sensible one.
Mylar dome
A thin polyester film dome. Light, so it is efficient, which is part of where the 90dB comes from. It is not as smooth as silk and not as extended as a good metal dome, but on a 4 inch coaxial fed by a head unit, efficiency is worth more than either.
Where these earn their keep
A 4 inch speaker is not going to give you midbass. Run these from roughly 120Hz up and let a 6.5 or a subwoofer do the rest, and they will do their job well. Ask them to be the whole system and they will not.
Who This Suits
Buy these if
- Your factory location is 4 inch and you are running head unit power.
- You want the loudest result available from an unamplified factory system.
- You are adding dash or rear fill to a system that already has bass covered.
- You accept a final sale on a discontinued product with no warranty path.
Look elsewhere if
- You need published depth or impedance before you commit.
- You want midbass from a 4 inch driver.
- Your location will take a 5.25 or a 6.5. Buy the bigger driver.
- You want warranty coverage or the option to return.
Installation
- Measure your depth. It is not published, so do not assume.
- High-pass at 120Hz or above if you have the means. On a head unit that usually means turning the bass control down.
- Wire straight from the head unit or amplifier. The crossover is built in.
- Check tweeter clearance behind the factory grille before you close the panel.
Condition and sale terms
Closeout stock from a discontinued Ground Zero line. Sold as a final sale with no returns, no exchanges and no manufacturer warranty. Packaging may show shelf wear from storage. Power handling, impedance, frequency response and mounting dimensions are not published by the manufacturer for this model and are not stated here. Once remaining stock is gone this listing will be removed.
Ask us to measure a pair before you buy: contact us.
| Type | 2-way coaxial |
|---|---|
| Woofer size | 4 inch |
| Cone | Polypropylene |
| Tweeter | Mylar dome |
| External crossover | None required, integrated |
| Condition | Closeout, discontinued |
| Sensitivity | 90 dB |
|---|
| Power handling | Not published |
|---|---|
| Impedance | Not published |
| Frequency response | Not published |
| Mounting depth and cutout | Not published |
Sensitivity is the only electrical figure Ground Zero published for this model. The rest is not documented in the material we hold.
