Performance Optimized Wedge Sealed 12" Enclosure Sundown Audio SA-12 · Single 12" Sealed enclosure

Yes. The SA-Classic 12, the SA-Series v.2 12 and the SA-Series v.3 12 share a basket within two tenths of an inch, in D2 and D4. The cutout is cut to the v.3 at 11.20 in and the depth clears the v.3's 8.4 in, so every generation and coil drops in. Each has its own Qtc in this box; the page lists all six.

1.00 cubic feet net, which is the sealed volume Sundown Audio themselves recommend for the SA-12, and the one cabinet covers every generation of the driver. In that volume the SA-Classic 12 lands at Qtc 0.69 (D2) and 0.67 (D4) with F3 at 46 and 49 Hz; the SA-Series v.2 12 lands at Qtc 0.63 (D2) and 0.63 (D4) with F3 at 61 and 54 Hz; and the SA-Series v.3 12 lands at Qtc 0.57 (D2) and 0.55 (D4) with F3 at 60 and 62 Hz. The Classic sits close to the Butterworth point; the v.2 and v.3 run drier and lean on cabin gain for the bottom octave, which is how Sundown voiced them. The box is 1.19 cu ft gross before the driver's displacement. Driver displacement is Sundown's own figure for each generation, and the largest, 0.18 cu ft for the v.3, is the one deducted.

Sundown rate the SA-Classic 12 at 1000 watts RMS, the v.2 at 1250 and the v.3 at 1500. Aim for roughly 70 to 100 percent of your generation's rating at the impedance you wire. A D2 coil carries two 2 ohm coils: 4 ohms in series or 1 ohm in parallel. A D4 coil carries two 4 ohm coils: 8 ohms in series or 2 ohms in parallel. Run the coils in series unless the amplifier is rated stable at the parallel load; 1 ohm is beyond most amplifiers.

The angled seat-side face matches the roughly 20 degree lean of a factory rear seat, so the cabinet sits flat against it instead of leaving a wasted triangle. The vertical trunk-lid-side face carries the driver, firing rearward into the trunk cavity.

A rectangular box of this volume wastes the triangle of space a leaning rear seat creates, and firing into the trunk lid rather than at the seat back gives the cabin a smoother path to the passengers. The wedge takes the same air volume and puts it where the car actually has room.

Half power lands between 46 to 62 Hz anechoic depending on the generation, before any cabin gain. Qtc runs 0.55 to 0.69 by generation and coil. These figures exclude cabin gain, which in most vehicles adds real output below 40 Hz. Sundown publish free-air resonance between 33.6 to 38.9 Hz across the six.

No. Polyfill is already installed as a light wall lining and the quantity is chosen so it does not change the acoustic volume. Do not add more.

No driver: this is an enclosure only. You receive the cabinet finished in plush black carpet, one side-mounted pre-wired terminal cup and the polyfill lining installed. Sundown Audio publishes no mounting hole locations for the SA-12, so the threaded inserts are not pressed 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 where the woofer's own holes fall when you mount it.