
Performance Optimized · Datasheet
Performance Optimized Wedge Ported 12" Enclosure | JL Audio 12TW1 Single 12" Ported enclosure
- Net volume
- 1.07 Cubic Feet
- Tuning
- 33.5 Hz
- Max mounting depth
- 4.606 Inches (JL Audio Spec)
- Cutout
- 11.063 Inches (JL Audio Spec)
- External dimensions
- 30.00 Inches W × 15.50 Inches H × 6.62 Inches / 12.27 Inches D
- Front baffle
- Vertical Baffle - Driver Fires Rearward Into The Trunk
- Alignment: 1.07 cu ft net vented at 33.5 Hz. F3 33.8 Hz anechoic, 1.43 dB passband ripple
- Driver: JL Audio 12TW1 -4, 300 W RMS, 10.0 mm Xmax, 32.40 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 12.27" D at base tapering to 6.62" D at top, 14.2 sq in port, ships dry
Technical specifications
| Series | Proline X Performance Optimized Wedge |
|---|---|
| Driver-Specific Fitment | JL Audio 12TW1 -4 (Dual 4 Ohm) |
| 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 | 6.62 Inches |
| Base Depth | 12.27 Inches |
| Internal Volume (Gross) | 1.44 Cubic Feet |
| Internal Volume (Net After Displacement) | 1.07 Cubic Feet |
| Port Type | Triangular Slot | Bottom-Rear Corner | Straight, No Bend | Side Exit |
| Port Geometry | Isosceles, 5.50 Inch Legs, 14.2 Square Inches, 25.26 Inches Long, Side Mouth |
| Port Tuning (Fb) | 33.5 Hz |
| Port Mouth | Triangle Through Side A, 1/2 In Roundover On All Three Edges, 24.2 Square Inches At The Face |
| Port Throat | Open Far End, 2.99 In Gap To Side B, 3/8 In Roundover On The Panel End |
| Port Air Velocity | 17.8 m/s In The Channel, 10.5 m/s At The Flared Mouth (17.0 m/s Chuff Threshold) |
| Predicted F3 | 33.8 Hz (Anechoic) |
| Passband Ripple | 1.43 dB (Anechoic) |
| Subsonic Filter | 26 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure |
| Driver Fs | 32.40 Hz |
| Driver Qts | 0.530 |
| Driver Qes / Qms | 0.560 / 11.070 |
| Driver Vas | 33.700 Liters / 1.190 Cubic Feet |
| Driver Sd | 436.0 Square Centimeters |
| Driver Mms | 194.00 g |
| Driver BL | 15.80 |
| Driver Re | 3.5 Ohm |
| Driver Xmax | 10mm (One-Way) |
| Driver Displacement | 0.07 Cubic Feet (Published by JL Audio) |
| Driver Sensitivity | 85.2 dB |
| Driver Power Handling | 300 Watts RMS |
| Driver Overall Diameter | 12.362 Inches (JL Audio Spec) |
| Mounting Depth Required | 4.606 Inches (JL Audio Spec) |
| Cutout Diameter | 11.063 Inches (JL 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 | Dual 4 Ohm |
| 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 | 210-300 Watts RMS (JL Audio Rated: 300W RMS) |
| Carpet Finish | Plush Black |
| Weight | 46 lb |
| Bundle Options | Enclosure Only (Bring Your Own JL Audio 12TW1) |
| Warranty | 1-Year Limited (Enclosure) |
| Manufactured | Tullahoma, Tennessee, USA |
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
1.07 cu ft net against a 33.7 L Vas, vented at 33.5 Hz.
03Perceived Ported vs Sealed
This cabinet, 1.07 cu ft net vented at 33.5 Hz, against JL Audio's recommended sealed box, 0.65 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 JL Audio's published 10.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
Installer's take
The shallowest twelve I cut: 6.62 inches at the top, 12.27 at the base, on a 4.61 inch motor. The port panel and the magnet ask for almost the same depth here, 6.05 against 5.95, and the panel wins by a tenth. 3.77 inches of flat floor stay clear in front of it for the braces.
300 watts and 10 mm of travel is a modest motor, and that is the trade for the depth. At rated power with the 26 Hz filter set the cone uses 6.1 mm, so there is reserve, but if you want output the 12W3v3 takes 500 watts in a cabinet two inches deeper. This one is for the trunk that has no depth to give.
Questions
Why is this enclosure tuned to 33.5 Hz?
A 32.4 Hz motor with a 0.53 Qts on 33.7 litres tunes cleanly a little above its resonance. 33.5 Hz gives 1.36 dB of in-car spread across 25 to 60 Hz on 1.43 dB of anechoic ripple, with an F3 of 33.8 Hz; the Down Fire version of the same driver reads 2.64 dB in the car. The port uses 25.26 of 25.77 inches of path and runs at 17.8 metres per second in the channel against an 18.2 limit, 10.5 at the mouth. 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 1.3 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 12.27 inches deep at the base and 6.62 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 JL Audio 12TW1 at 61 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?
JL Audio rate the 12TW1 at 300 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 61 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 JL Audio's recommended sealed box, 0.65 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 2.99 inch gap at the far end and exits through the side panel as the same triangle. Straight, no bend: 25.26 inches of path and 14.2 square inches of channel running at 17.8 metres per second, 54 percent of its turbulence limit. The three mouth edges are rounded over at 1/2 inch, so the opening at the face is 24.2 square inches and the air leaves it at 10.5 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 25.26 inches for 33.5 Hz. Stuff it and you move the tuning without shortening the port.
Is the 12TW1 included?
No. This is an enclosure only, cut for the JL Audio 12TW1 specifically: the 11.063 inch cutout, the 4.606 inch mounting depth allowance and the 1.07 cubic foot alignment all come from JL Audio's published parameters. It fits both coil versions; the alignment published here is the -4. Bring your own driver.
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