Connected to upgrade the Bose Acoustimass 5 to a QSC2450 amplifier, easily handles 700 watts at 2 ohms. Pleasant sound and deep bass, but definitely pay attention to the outer diameter of 17 cm. For such a small housing, it really delivers solid power.

Feels really solid, but I still need to try it out – at first glance, it gives a really well-made impression.

Really good speaker, delivers exactly what was promised.

A 16 cm Subwoofer in the car is always a compromise, but Ground Zero really shows how well it can still work. At first glance, the thing looks incredibly robust, especially the huge magnet.

The chassis needs a lot of power, at least 250 W RMS. In a closed housing, there isn't much level, little depth, and too much excursion. Also, the Subwoofer builds quite deep, which is hardly surprising given the large magnet with pole core drilling.

In a bass reflex housing with enough power, it really performs well. I planted it in my glove compartment (sealed and reinforced with fiberglass and cement, 5.5 liters gross, external port with HT tube) and was about to cancel my planned trunk build with large woofers. I actually just wanted to relieve the door woofers, but in the end, it even replaced my GZHW 25X in the trunk. Although it was installed in a closed box, the "cabin gain" is even stronger in my liftback. For such a small monster, it's really impressive performance.

Full recommendation, even though more diaphragm area is always better when space and volume allow it.

These little beasts really blew me away. I built a housing in my car, each chamber has 20 liters and 70 mm x 50 cm bass reflex tubes. The bass sounds like it's coming straight from hell. I used to have a 25 cm Subwoofer from Ground Zero from 2011 in a bandpass, which then broke. Since I wanted more space in the trunk (E39 sedan with ski pass opening), I switched to the 16.5 cm – and what Ground Zero delivers here in terms of power is just brutal. Also, it's really impressive how stiff the diaphragm sits in the chassis and how much power is behind the extreme excursion.