Ground Zero GZTB300BR 12 inch Bass Box
Carpeted classically shaped trapezoidal ported box loaded with a 12 inch GZTW 30T woofer from Ground Zero’s Titanium range, with diamond pattern steel plate end panels. One end plate bears the 4mm squeeze posts. These are a better than normal type seen on many woofers but have knurled tops and a well made banana plug will fit in its end nicely as well as likely fit through the terminal as well. The driver has an indented concave dust dome and a coated gritty-feeling surfaced cone and a large top roll surround. The grille is a frame type and the black carpet covering has the branding embroidered neatly into the top panel. Also, the gas flowed port has the Ground Zero logo.
– Frequency response: not quoted
– Power Handling: 400w RMS
– GZTW 30T Titanium series driver
– Pressed Steel chassis
– Large rubber top roll surround
– Single 4 Ohm voice coil
– Bright plated 4mm squeeze post terminals
– Voice Coil Diameter: 2 inch (50mm)
– Dimensions: (WxHxD) 550 x 390 x 260mm
– Volume: 45 litres / 1.59 cubic feet
– Driver Xmax: 14mm
– Driver Fms: 25Hz
– Driver Qts: 0.58
– Driver Vas: 110.6 Litres
Review by Adam Rayner
Basically if you like classical music then stop here and go read about me getting tearful at the second triangle on the left in the Morel Ultimo 12 review all £600 of raw woofer of it! This is balls out bass head throb-master product.
Ground Zero’s whole attitude and existence has always been extreme, from their first ever launch from a tiny stand at a Las Vegas CES show to going to Germany and evolving to justify the apocalyptic series names of Plutonium and Nuclear and the like! From the ‘merest’ range of Titanium woofers, they take the 12 and simply port it like they feel it aughta be done.
I felt it aughta have a fair test so I played some la-la pom-pom music (a bit of my beloved Spirit of Sound #6 disc which I thought I had lost and had been sent to Clarion in a deck! Huge thanks for sending it back, Sweetie!) and was not impressed.
It has a big old coil for a fat arsed 400w RMS. Not piffle speak but German engineered. This means 800w peak are easy and it’ll do more for a moment. This makes for a big old moving mass. Yet GZ want a deep wobbly throb, so it’s in a well wobbly and compliant suspension. This adds up to a lack of super-tightness that you’ll find up the ranges above and a low pure-SQ score.
But that’s to miss the point altogether, just look at the VFM score! Because what you get is good eating for the bass hungry. I immediately played some More Bass More Boom, More Bottom by Power Supply and for once in a very rare while played the entry track all the way through. It finishes in the sounds of Beavis and Butthead chuckling and Beavis says, ‘that makes me want to like push something over!’
I moved it on to outrageous Woofer Excursion Test track with all its portentous warnings about reducing the volume level. But, erm, there’s no easy way to say this, I was going into the bedroom to throw away the tub from some instant cup noodles from the pound shop I’d had for lunch and didn’t make it back to the hallway in time. I failed to catch it before the quite inappropriately powerful (for this application) JBL GTO 24001 monoblock that is the Talk Audio reference bass bucket ‘o D Class wellie, had booted it. There was one brief but painfully loud clack as I frankly abused the living shit out of the poor bloody thing.
I was Jezza Clarkson quite hooliganistically bursting the tyres on a Bentley, hooning the airfield on Top Gear. I thought it had to be screwed but the woofer just didn’t care. I had found, just like the bloody CD had suggested, the limit of my subwoofer’s suspension but it played on. Furthermore, I continued to crank it but with a little more sense. Of course I once again had to give it the sudden kilowatt peak a few more times to see if it’d die of it but it just carried on. Of course this is stupid but I do it for you! The thing is, though, that it sounds good for dance and pop bass at low levels and as you crank it up, you find the pass band of the tuning of that port is nice and wide and while it really throbs yer butt off in the hump zone around the 40Hz point, it will drop to proper throbby stuff and yes, you and one amp and one box can play slow jams and stuff. Just try not to load it up with an amp way above the 400w RMS rating. Personally, I’d be happy to see a 500 watter drive it, as long as the gain wasn’t cranked round too far on the amp’s end panel.
A great intro the Ground Zero brand (by the way, named long before 9/11, just unluckily-named, like Tsunami) and no piffly weedy option. You will fill a hatch back and if you haven’t got too much car in between you and the box, I reckon you’ll drive in a 120- 130dB sound field if you have the watts.
The GZTB 300BR bass box – enough bass to really piss off the neighbours! And you can quote me!
Sound Quality 7.0
Build Quality 8.0
Power Handling 9.0
Efficiency 8.0
Value For Money 9.0
Overall rating 8.2