

Performance Optimized · Datasheet
Performance Optimized Wedge Ported 12" Enclosure Sundown Audio LCS v.2 12" Subwoofers · Single 12" Ported enclosure
- Net volume
- 1.37 Cubic Feet
- Tuning
- 33.5 Hz
- Max mounting depth
- 5.500 Inches (Sundown Audio Spec)
- Cutout
- 11.120 Inches (Sundown Audio Spec)
- External dimensions
- 30.00 Inches W × 15.50 Inches H × 8.25 Inches / 13.89 Inches D
- Front baffle
- Vertical Baffle - Driver Fires Rearward Into The Trunk
- Alignment: 1.37 cu ft net vented at 33.5 Hz. F3 34.9 Hz anechoic, 1.40 dB passband ripple
- Driver: Sundown Audio LCS v.2 12" Subwoofers S8, 500 W RMS, 14.0 mm Xmax, 31.59 Hz Fs
- Build: Rear-firing wedge, 20 degree rear rake, V-groove and dado joinery, triangular side-exit slot port with a 1/2" rounded mouth, double 1.5" baffle, side-mounted terminal cup
- Cabinet: 30.00" W x 15.50" H x 13.89" D at base tapering to 8.25" D at top, 18.4 sq in port, ships dry
Spec of record
Technical specifications
| Series | Proline X Performance Optimized Wedge |
|---|---|
| Driver-Specific Fitment | Sundown Audio LCS v.2 12" Subwoofers S8 (S8) |
| Enclosure Type | Ported | Rear-Firing Trunk Wedge |
| Baffle Configuration | Vertical Baffle - Driver Fires Rearward Into The Trunk |
| Wedge Angle | 20 Degrees On The Rear (Seat-Side) Panel |
| External Width | 30.00 Inches |
| External Height | 15.50 Inches |
| Top Depth | 8.25 Inches |
| Base Depth | 13.89 Inches |
| Internal Volume (Gross) | 1.80 Cubic Feet |
| Internal Volume (Net After Displacement) | 1.37 Cubic Feet |
| Port Type | Triangular Slot | Bottom-Rear Corner | Straight, No Bend | Side Exit |
| Port Geometry | Isosceles, 6.25 Inch Legs, 18.4 Square Inches, 25.11 Inches Long, Side Mouth |
| Port Tuning (Fb) | 33.5 Hz |
| Port Mouth | Triangle Through Side A, 1/2 In Roundover On All Three Edges, 29.5 Square Inches At The Face |
| Port Throat | Open Far End, 3.14 In Gap To Side B, 3/8 In Roundover On The Panel End |
| Port Air Velocity | 19.2 m/s In The Channel, 11.9 m/s At The Flared Mouth (17.0 m/s Chuff Threshold) |
| Predicted F3 | 34.9 Hz (Anechoic) |
| Passband Ripple | 1.40 dB (Anechoic) |
| Subsonic Filter | 26 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure |
| Driver Fs | 31.59 Hz |
| Driver Qts | 0.518 |
| Driver Qes / Qms | 0.573 / 5.418 |
| Driver Vas | 48.780 Liters / 1.723 Cubic Feet |
| Driver Sd | 457.4 Square Centimeters |
| Driver Mms | 154.57 g |
| Driver BL | 19.44 |
| Driver Re | 7.1 Ohm |
| Driver Xmax | 14mm (One-Way) |
| Driver Displacement | 0.07 Cubic Feet (Published by Sundown Audio) |
| Driver Sensitivity | 86.5 dB |
| Driver Power Handling | 500 Watts RMS |
| Driver Overall Diameter | 12.500 Inches (Sundown Audio Spec) |
| Mounting Depth Required | 5.500 Inches (Sundown Audio Spec) |
| Cutout Diameter | 11.120 Inches (Sundown Audio Spec) |
| Material | Langboard Elite 3/4" MDF |
| Construction | ShopSabre CNC / Two Windowed C Braces At The Third Points, Seated On The Port Panel |
| Joinery | V-Groove and Dado (CNC-Cut) |
| Front Baffle Construction | Double-Layer 1.5" MDF | Cosmetic Front Layer Routed For The Acrylic Insert |
| Mounting Hardware | Threaded Inserts At Every Mounting Location | Stainless Steel Machine Screws Included |
| Voice Coil Configuration | S8 |
| Terminal Cup | Proline X ABS/Carbon Fiber Composite | Side Mounted, Opposite The Port | 12g OFC Pre-Wired |
| Damping | None - Ships Dry. Polyfill Detunes A Ported Enclosure |
| Recommended Power | 350-500 Watts RMS (Sundown Audio Rated: 500W RMS) |
| Carpet Finish | Plush Black |
| Weight | 49 lb |
| Bundle Options | Enclosure Only (Bring Your Own Sundown Audio LCS v.2 12" Subwoofers) |
| Warranty | 1-Year Limited (Enclosure) |
| Manufactured | Tullahoma, Tennessee, USA |
Modelled response
Performance in this enclosure
01Is this driver right for a ported box?
Efficiency bandwidth product places the motor before anything else is decided.
02What the box does to it
1.37 cu ft net against a 48.8 L Vas, vented at 33.5 Hz.
03Perceived Ported vs Sealed
This cabinet, 1.37 cu ft net vented at 33.5 Hz, against Sundown Audio's recommended sealed box, 1.00 cu ft.
04Real World Ported vs Sealed
The same two boxes with cabin gain applied, 45 Hz corner, 18 dB ceiling.
05The watts that reach Xmax (in this enclosure)
Travel scales with the square root of power, so there is one wattage that puts the cone exactly on Sundown's published 14.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
From the shop floor
Installer's take
The LCS v.2 12 carries 48.78 litres of Vas on a 31.59 Hz resonance, a compliant motor. I vent it at 33.5 Hz in 1.371 cubic feet net and the model gives back a 34.9 Hz anechoic F3 on 1.4 dB of ripple, inside our 4.5 dB cap. Sundown publishes no sealed number for this driver, so I am not weighing it against one.
The port is a 6.25 inch leg triangle, 18.4 square inches. At the driver's rated 500 watts the channel runs 19.2 metres per second and the mouth 11.9, under the 17 where a slot port starts to chuff.
This one ships as a single 8 ohm coil, so there is no wiring decision, just the one load. The base lands at 13.89 inches, set by the port panel clearing the motor at 7.70 inches against 6.84 for the magnet alone, and it stays inside the cabinet's own 15.5 inch height.
It ships dry. Do not add polyfill to a ported box. Set your subsonic filter at 29 Hz.
Before you order
Questions
Why is this enclosure tuned to 33.5 Hz?
A 0.5183 Qts on 48.78 litres of Vas is a compliant motor, and 33.5 Hz keeps the ripple to 1.4 dB, inside the 4.5 dB cap. Sundown does not publish a sealed box for the LCS v.2 12 to weigh this against. At the driver's rated 500 watts the channel runs at 19.2 metres per second and the mouth at 11.9, under the 17 where a slot port starts to chuff. The base depth of 13.89 inches is set by the port panel clearing the motor at 7.70 inches, not the 6.84 inch magnet top, and it stays under the cabinet's own 15.5 inch height. Tuning is chosen for in-car response rather than an anechoic curve: a vehicle adds roughly 12 dB per octave below about 45 Hz. In this cabinet that lands at 1.2 dB of in-car spread across 25 to 60 Hz.
Why the 20 degree wedge, and why rear-firing?
The raked face is the seat side. A factory rear seat back leans about 20 degrees off vertical, so the cabinet sits flat against it and uses floor a square box wastes. The baffle stays vertical and fires rearward into the trunk, which acts as the acoustic extension into the cabin. This one is 13.89 inches deep at the base and 8.25 at the top, 30.00 wide and 16 tall.
Do I need a subsonic filter?
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 Sundown Audio LCS v.2 12" Subwoofers at 59 percent of its usable travel at full rated power; without it there is no meaningful number to quote.
How much power can I run, and at what impedance?
Sundown Audio rate the LCS v.2 12" Subwoofers at 500 W RMS and that is the thermal ceiling. The Performance Graphs tab shows the mechanical limit, the power at which the cone reaches the end of its travel in this cabinet: here the cone sits at 59 percent of usable travel at the rating, so heat is what stops you, not travel. A D2 coil is 4 ohms in series or 1 ohm in parallel; run series unless the amplifier is rated for 1 ohm. A D4 is 8 series or 2 parallel.
Would a sealed box be better for me?
The two alignments converge at the bottom of the band on this driver rather than crossing cleanly, so there is no meaningful subsonic advantage either way. Above 25 Hz the vent is the louder of the two. The Performance Graphs tab plots this cabinet against Sundown Audio's recommended sealed box, 1.00 cu ft.
How does the side port work?
It is a triangular slot in the bottom-rear corner: the floor and the raked back wall are two sides, one bevelled panel is the third. It runs across the cabinet, opens into the box through a 3.14 inch gap at the far end and exits through the side panel as the same triangle. Straight, no bend: 25.11 inches of path and 18.4 square inches of channel running at 19.2 metres per second, 55 percent of its turbulence limit. The three mouth edges are rounded over at 1/2 inch, so the opening at the face is 29.5 square inches and the air leaves it at 11.9 metres per second against the 17.0 threshold where a slot port starts to chuff; the panel's throat end is rounded at 3/8 inch for the same reason. The terminal cup is on the other side.
Does this enclosure ship with polyfill?
No, and do not add any. Every sealed Proline X enclosure ships with polyfill; a ported one must not, because damping changes the effective volume the port is tuned against. The port here is cut to 25.11 inches for 33.5 Hz. Stuff it and you move the tuning without shortening the port.
Is the LCS v.2 12" Subwoofers included?
No. This is an enclosure only, cut for the Sundown Audio LCS v.2 12" Subwoofers specifically: the 11.120 inch cutout, the 5.500 inch mounting depth allowance and the 1.37 cubic foot alignment all come from Sundown Audio's published parameters. It fits both coil versions; the alignment published here is the S8. Bring your own driver.
Same series, same size
Alpine R2-W12
Alpine RSW12
Alpine S2-W12
Arc Audio 10" Arc Series
Audiofrog GB12
Dual Kicker Solo X 12" Subwoofers
Hertz Mille Pro MPS 300