Professional Series Ported 15" Enclosure Ground Zero GZHW 38 · Single 15" Ported enclosure

A 0.7700 Qts on 22.19 litres of Vas, backed by a 0.8400 Qes and a 10.0200 Qms, is a compliant motor that wants a large box and a low vent, and 34.0 Hz brings F3 to 28.2 Hz on 2.24 dB of ripple. At the driver's rated 1500 W the port runs 16.3 metres per second through the mouth at 1800 W, the reference point the velocity check is measured against. The 855.3 square centimetre Sd behind this solve is not a Ground Zero figure: Ground Zero publishes no cone area for the GZHW 38, so the number is estimated. Tuning is chosen for in-car response rather than an anechoic curve: a vehicle adds roughly 12 dB per octave below about 45 Hz, and this tuning is where that sum comes out flattest across 25 to 60 Hz.

Every driver is run through the Performance Optimized wedge and down-fire before this chassis; the Professional box is where a driver lands when that smaller envelope, 30 inches wide and 18 inches deep with a triangular side port, cannot give it what it needs at its rated power. The GZHW 38 did not clear the port gate there. The calmest wedge port that fits that envelope is 32.0 square inches at 26.0 by 11.25 by 17.98 inches, and its mouth runs 23.8 metres per second at 2000 W against the 17 metres per second line where a port starts to chuff. That port would stay clean to about 1024 W. The slot on this box reaches 66.0 square inches and holds the mouth at 16.8 metres per second at 2400 W. An under-ported box does not fail quietly. Air speed at the mouth rises with power; past the chuff line the flow turns turbulent and the port is audible on every note. The turbulence also chokes the port, so the box behaves as if it were tuned higher than it is, loses output near tuning, and lets the cone travel further below tuning than the design allows. This chassis is a full-size front-firing box on a 2.25 inch baffle built from three 3/4 inch layers with the woofer flush-mounted in the outer layer, a Ground Zero logo acrylic, and a port and excursion budget checked at 2400 W. It carries a 2 year warranty against 1.

Ground Zero does not publish the mounting hole locations for the GZHW 38, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: 8 to 12 inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, an allen key and woofer gasket tape. You set the inserts when you mount the woofer; one kit serves one woofer. A dual cabinet ships two kits.

Yes, at 27 Hz, 24 dB per octave. Below tuning a vented box stops loading the cone and excursion runs away toward DC. With the filter in place this cabinet puts the Ground Zero GZHW 38 at 50 percent of its usable travel at 2400 W.

Not one we can show you. We do not build a sealed enclosure for the Ground Zero GZHW 38 and Ground Zero publish no sealed volume for it, so the Performance Graphs tab carries no ported-versus-sealed chart: the only sealed box left to plot would be this cabinet stuffed and sealed, which nobody would build, and a comparison against it would tell you nothing you could buy. What a vented box gives up is the region below tuning, where the cone unloads and the 27 Hz subsonic filter takes over; around 34.0 Hz the vent carries the load and cone travel drops to its minimum, which no sealed alignment can do.

It is a vertical slot beside the woofer, the full height of the cavity, 4.00 inches wide and 66.0 square inches. It runs 10.25 inches to the back wall and turns once along it for 19.44 inches; the fold costs about 1.5 Hz and the port is cut for it. The channel runs at 22.3 metres per second at 2400 W, 37 percent of its turbulence limit, and the mouth edges carry a 1/2 inch roundover so the air leaves the face at 16.8 metres per second against the 17 metres per second threshold where a slot starts to chuff.

74 lb, 36.00" W x 18.00" H x 18.00" D external. It ships as a UPS parcel; the price includes shipping in the 48 states. Every Professional cabinet is priced the same way, by its size: this one is 6.75 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 74 lb parcel and checkout adds nothing. Do not add polyfill; it ships dry on purpose.

No. This is an enclosure only, cut for the Ground Zero GZHW 38 specifically: the 14.170 inch cutout, the 9.090 inch mounting depth allowance and the 3.09 cubic foot alignment all come from Ground Zero's published parameters. It fits both coil versions; the alignment published here is the D1 or D2. Bring your own driver.