Ground Zero
Ground Zero GZIW 10SPL 10″ high quality SPL subwoofer
Ground Zero GZIW 10SPL 10″ high quality SPL subwoofer
Closeout, remaining stock
Ground Zero GZIW 10SPL 10 Inch SPL Subwoofer
German-engineered 10 inch SPL driver. Klippel-optimized motor, 25mm Xmax, 700W power handling, aluminium cast basket. Discontinued line, remaining stock only.
- Closeout
- Discontinued
- Klippel verified
- Final sale
What You Are Buying
A 10 inch SPL subwoofer from Ground Zero's Iridium line, built around a Klippel-optimized motor and rated for 700W. Ground Zero has discontinued this model and we are not restocking it, so what is on the shelf is what exists.
Klippel optimization matters more than the marketing usually explains. A Klippel analyser measures how a motor actually behaves through its full stroke rather than at rest, which exposes where force falls off and where the suspension stops being linear. A driver tuned against that data holds its behaviour further out into its excursion instead of collapsing into distortion near the limits. That is the difference between a subwoofer that gets loud and one that stays composed while it does.
Read this before you buy
Final sale. No returns, no exchanges, no manufacturer warranty. This is a discontinued model with no replacement pipeline, so a failed driver cannot be swapped for a matching one. If you need warranty coverage, buy current production.
Reading the Parameters
The published Thiele-Small set tells you most of what you need to know about how this driver wants to be loaded.
Fs 40.8 Hz
Free-air resonance sits at 40.8Hz, which is high for a 10 inch subwoofer and is a deliberate SPL design choice. A higher Fs concentrates output in the 40 to 60Hz band where most bass content and most SPL scoring lives, at the cost of subterranean extension. This is not the driver for reproducing a 25Hz pipe organ note. It is the driver for making a kick drum hit hard.
Qts 0.62
Total Q of 0.62 is firmly in sealed territory. A driver in this range wants a modest sealed box and rewards it with controlled, accurate response. It can be ported, but the enclosure has to be designed around the parameters rather than borrowed from a generic chart, and the gain comes with a steeper rolloff below tuning.
Vas 14.3 L
Equivalent compliance volume of 14.3 litres is small, which is good news for the install. A low Vas means the driver does not need a large enclosure to work properly, so this fits in vehicles where a big box is not an option.
Xmax 25mm and BL 16 Tm
25mm of linear excursion is genuine long-throw territory, and a BL factor of 16 Tm is a strong motor. Together they are what allows 700W of power handling to turn into displacement rather than heat. The tradeoff is efficiency: at 84dB this driver is not sensitive, and it will not do anything impressive on a small amplifier.
What the numbers add up to
High Fs, high Qts, low Vas, long Xmax, low sensitivity. That combination describes a compact sealed SPL driver that wants real power and gives back punch in the 40 to 60Hz band rather than deep extension. Size the amplifier accordingly.
Enclosure
Sealed is the natural alignment here and it is what we would build for it. Working from the published parameters, a net 0.8 cubic foot sealed chamber is the target. Once you add driver displacement, bracing and material, gross internal volume lands close to 1.0 cubic foot.
| Net internal volume | 0.8 cubic feet |
|---|---|
| Driver displacement | 0.08 cubic feet (estimated) |
| Bracing and material | 0.05 cubic feet (estimated) |
| Gross internal volume | Approximately 1.0 cubic foot |
| Polyfill | Recommended, light fill |
We build enclosures cut to this driver on our own CNC in Tullahoma. If you want one, contact us with your vehicle and the space you have and we will tell you what fits.
Power and Wiring
This driver wants real current. The published figures point at 450 to 500W RMS depending on final impedance, and the electrical system has to support that rather than sag under it.
- Amplifier. A monoblock in the 500W RMS range at the impedance you wire to. The amplifier must be stable at that load, not merely rated for it on paper.
- Alternator. A stock 120 to 140A alternator is adequate for a single driver at this power. Two of them is a different conversation.
- Power wire. 4 AWG minimum, and OFC rather than copper-clad aluminium if you have the choice.
- Ground. 4 AWG to bare chassis metal within 18 inches of the amplifier. A long or painted ground undoes everything else.
- Fuse. 60 to 80A within 18 inches of the battery.
- Voltage. Hold above 12.5V at the amplifier terminals under sustained load. Below that you are clipping regardless of how the gain is set.
Setting gain
Set it with an oscilloscope or a distortion detector, not by ear and not by turning it up until it sounds loud. A driver with this much motor will happily convert a clipped signal into voice coil heat, and thermal failure is not a warranty event on a discontinued closeout.
Who This Suits
Buy this if
- You want maximum output from a compact sealed box and have 450 to 500W to give it.
- Your listening is kick drum and bass guitar rather than sub-30Hz effects.
- Your electrical system is sorted, or you are willing to sort it.
- You accept a final sale on a discontinued driver with no warranty path.
Look elsewhere if
- You want deep extension. High Fs and high Qts is the wrong recipe for that.
- You are running a 200 to 300W amplifier. At 84dB sensitivity this will underwhelm.
- You need a large ported box for maximum efficiency; the parameters do not favour it.
- You want warranty coverage or the option to return.
Construction
- Aluminium cast basket. Rigid under load and a better heat path than a stamped steel frame, which matters on a driver expected to run hard.
- Klippel-optimized motor. Tuned against measured large-signal behaviour rather than small-signal assumptions.
- Long-throw suspension. Built to support 25mm of linear travel without the spider going non-linear early.
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. Thiele-Small parameters are as published by Ground Zero; enclosure figures marked estimated are our own calculation and not manufacturer data. Once remaining stock is gone this listing will be removed.
Questions on enclosure sizing or amplifier matching before you buy: contact us.
| Fs, free-air resonance | 40.8 Hz |
|---|---|
| Qts, total Q | 0.62 |
| Vas, equivalent compliance | 14.3 litres |
| Xmax, linear excursion | 25mm |
| BL factor | 16 T·m |
| Efficiency | 84 dB |
| Type | 10 inch SPL subwoofer |
|---|---|
| Series | Ground Zero Iridium |
| Power handling | 700W |
| Recommended amplifier | 450 to 500W RMS at final impedance |
| Basket | Aluminium cast |
| Motor | Klippel optimized |
| Condition | Closeout, discontinued line |
| Net internal volume | 0.8 cubic feet |
|---|---|
| Driver displacement | 0.08 cubic feet (estimated) |
| Bracing and material | 0.05 cubic feet (estimated) |
| Gross internal volume | Approximately 1.0 cubic foot |
| Polyfill | Recommended, light fill |
| Alternator | 120 to 140A minimum for a single driver |
|---|---|
| Power wire | 4 AWG minimum, OFC preferred |
| Ground wire | 4 AWG to chassis within 18 inches |
| Fuse | 60 to 80A within 18 inches of the battery |
| Voltage under load | Hold above 12.5V at the amplifier |
Thiele-Small parameters are as published by Ground Zero. Enclosure volumes marked estimated are our own calculation from those parameters, not manufacturer data.
