Professional Series Ported 12" Enclosure American Bass HD Velocity 12 · Single 12" Ported enclosure

Sealed, the HD Velocity 12 needs 0.17 cubic feet net to reach a Qtc of 0.707. Vented, it trades that for deeper extension. The slot is gated at 2640 W, 1.2 times American Bass's rating: the channel runs 21.7 m/s and the mouth 16.8, and the cone peaks at 14.0 of its 17.5 mm with the subsonic filter in place. 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 HD Velocity 12 did not clear the port gate there. The calmest wedge port that fits that envelope is 24.7 square inches at 29.0 by 12.25 by 17.89 inches, and its mouth runs 29.4 metres per second at 2200 W against the 17 metres per second line where a port starts to chuff. That port would stay clean to about 734 W. The slot on this box reaches 68.9 square inches and holds the mouth at 16.8 metres per second at 2640 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, an American Bass logo acrylic, and a port and excursion budget checked at 2640 W. It carries a 2 year warranty, against 1 year on the Performance Optimized lines.

American Bass does not publish the mounting hole locations for the HD Velocity 12, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: 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, and this box ships with one kit.

Yes, at 26 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 American Bass HD Velocity 12 at 80 percent of its usable travel at 2640 W.

Not one we can show you. We do not build a sealed enclosure for the American Bass HD Velocity 12 and American Bass 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 26 Hz subsonic filter takes over; around 32.5 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, 4.75 inches wide and 68.9 square inches. It runs 16.25 inches to the back wall and turns once along it for 11.38 inches; the fold costs about 1.5 Hz and the port is cut for it. The channel runs at 21.7 metres per second at 2640 W, 35 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.

75 lb, 32.00" W x 16.00" H x 24.75" D external. Every Professional cabinet is priced the same way, by its size: this one is 7.33 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 75 lb parcel and checkout adds nothing. Do not add polyfill; it ships dry on purpose.

No. This is an enclosure only, cut for the American Bass HD Velocity 12 specifically: the 11.340 inch cutout, the 9.020 inch mounting depth allowance and the 3.61 cubic foot alignment all come from American Bass's published parameters. It fits both coil versions; the alignment published here is the D1. Bring your own driver.