Professional Series Ported 12" Enclosure | Sundown Audio SA-12

Sundown publishes a Qts of 0.428 for the SA-12 v.3 D2, and it agrees with their own Qes of 0.525 and Qms of 2.308. The gate here is measured at the coil's rated power, 1500 W, and the port stays clean past that rating, modeled to 1697 W before mouth velocity becomes the limiting factor. The v.2 and the Classic are rated lower, 1250 W and 1000 W, so they sit further inside the same port. Ripple across the passband holds at 2.56 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 SA-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 11.62 by 17.27 inches, and its mouth runs 22.4 metres per second at 1500 W against the 17 metres per second line where a port starts to chuff. That port would stay clean to about 865 W. The slot on this box reaches 32.6 square inches and holds the mouth at 16.0 metres per second at 1500 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 1500 W. It carries a 2 year warranty against 1.

Sundown Audio does not publish the mounting hole locations for the SA-12, 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 Sundown Audio SA-12 at 45 percent of its usable travel at 1500 W.

Below about 23 Hz, yes. The sealed wedge we build for it is louder down there by up to 3.7 dB, because a sealed box rolls off gently into the subsonic region where a vented one falls away steeply once it is under tuning. Above that this alignment is the louder of the two for the same power. The Performance Graphs tab plots this cabinet, 1.66 cubic feet vented at 34.5 Hz, against the 1.00 cu ft sealed wedge we build for this driver (PO 12-S W SA12), so you can see exactly where they cross.

It is a vertical slot beside the woofer, the full height of the cavity, 2.25 inches wide and 32.6 square inches. It runs 7.50 inches to the back wall and turns once along it for 21.47 inches; the fold costs about 1.5 Hz and the port is cut for it. The channel runs at 24.7 metres per second at 1500 W, 52 percent of its turbulence limit, and the mouth edges carry a 1/2 inch roundover so the air leaves the face at 16.0 metres per second against the 17 metres per second threshold where a slot starts to chuff.

70 lb, 32.00" W x 16.00" H x 13.50" 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 4.00 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 70 lb parcel and checkout adds nothing. The Performance Optimized 12 inch ported wedge is $399.99. The $80 difference is the larger box and the port this driver needs to run at its rating. Do not add polyfill; it ships dry on purpose.

No. This is an enclosure only, cut for the Sundown Audio SA-12 specifically: the 11.200 inch cutout, the 8.400 inch mounting depth allowance and the 1.66 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.