Professional Series Ported 12" Enclosure Sundown Audio X-Series v.3 12 · Single 12" Ported enclosure

Sundown publishes a Qts of 0.490 for the X-Series v.3 12 D2, and the figure checks out against their own Qes of 0.540 and Qms of 4.820. Sundown does not recommend this driver sealed; their own ported figure is 2.50 cubic feet at 32 Hz through a 40 square inch port, and they say it runs in up to a 50 percent larger box. This cabinet is larger, because the gate here is measured at the coil's rated power, 2500 W, and keeping the slot mouth under 17 metres per second at that power takes 72.5 square inches of port, which is what sets the 27.5 inch depth; in Sundown's 2.50 cubic feet no port that fits can hold that velocity. The port stays clean to 2514 W before mouth velocity becomes the limiting factor, the cone peaks at 16.7 of its 30.0 mm at rated power, and ripple across the passband holds at 5.97 dB. 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 X-Series v.3 12 did not clear the port gate there. The calmest wedge port that fits that envelope is 19.9 square inches at 23.5 by 12.12 by 17.77 inches, and its mouth runs 34.7 metres per second at 2500 W against the 17 metres per second line where a port starts to chuff. That port would stay clean to about 599 W. The slot on this box reaches 72.5 square inches and holds the mouth at 17.0 metres per second at 2500 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 Sundown Audio logo acrylic, and a port and excursion budget checked at 2500 W. It carries a 2 year warranty, against 1 year on the Performance Optimized lines.

Sundown Audio does not publish the mounting hole locations for the X-Series v.3 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 24 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 Sundown Audio X-Series v.3 12 at 56 percent of its usable travel at 2500 W.

Not one we can show you. We do not build a sealed enclosure for the Sundown Audio X-Series v.3 12 and Sundown Audio mark it Not Recommended for a sealed enclosure, 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 24 Hz subsonic filter takes over; around 31.0 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, 5.00 inches wide and 72.5 square inches. It runs 18.75 inches to the back wall and turns once along it for 8.86 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 2500 W, 35 percent of its turbulence limit, and the mouth edges carry a 1/2 inch roundover so the air leaves the face at 17.0 metres per second against the 17 metres per second threshold where a slot starts to chuff.

88 lb packed, 32.00" W x 16.00" H x 27.50" D external. This cabinet is 8.15 cubic feet outside. Delivery to the 48 states is inside the price; it ships as an 88 lb parcel and checkout adds nothing. Do not add polyfill; it ships dry on purpose.

No. This is an enclosure only, cut for the Sundown Audio X-Series v.3 12 specifically: the 11.090 inch cutout, the 9.670 inch mounting depth allowance and the 4.12 cubic foot alignment all come from Sundown Audio's published parameters. It fits both coil versions; the alignment published here is the D2. Bring your own driver.