JL Audio
12TW1-4
300W RMS 12" SVC Subwoofer

$399.99
JL Audio 12TW1-4
JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4 JL Audio 12TW1-4

Overview

Built on JL Audio's patented thin-line subwoofer technology, the 12TW1 delivers a powerful combination of shallow mounting depth and excursion capability, while operating in insanely small enclosures (0.65 cu.ft. / 18.4 liters). This, combined with a special cast alloy frame design, makes the 12TW1 capable of operating in extremely tight spaces. These include under-seat installations in trucks, 2-seat sports cars and many other creative applications requiring a compact, low profile subwoofer design.

JL Audio's patented thin-line woofer technology compresses the architecture of the 12TW1 using a "concentric tube" structure built into the injection-molded cone body. This structure supports the voice coil and a full annular spider, while permitting the placement of a large motor structure further forward in the speaker than with conventional designs.

The 12TW1 also features a clever frame design that minimizes the frontal clearance required for the excursion of the driver. This is accomplished by recessing the suspension attachment surface, so that most of the forward excursion occurs within the frame's dimensions. Thanks to this feature, the 12TW1 requires only 0.87” (22 mm) of frontal clearance, even with its grille installed. This allows for more efficient use of space and increased enclosure volume within a given overall depth.

Even though the 12TW1 is optimized for an enclosure much smaller than any other JL Audio twelve-inch Subwoofer, it never sounds like a big woofer struggling in a tiny box...instead, it delivers all the rich, deep, controlled bass you have come to expect from a JL Audio subwoofer system.

  • Very shallow mounting depth (4.62” / 117 mm)
  • No pole vent: permits mounting close to rear wall of enclosure
  • Extremely small sealed enclosure volume requirements
  • Long linear excursion capability (0.40” / 10 mm, one-way)
  • DMA-optimized motor design
  • Patented "concentric tube" architecture
  • Patented “floating cone attach method” technology
  • Cast alloy frame with flat edges for tight driver grouping
  • Injection molded, mica-filled polypropylene cone
  • Rubber surround
  • Steel mesh grille included with each driver
  • Precision-built in USA at JL Audio’s Miramar, Florida factory with global components

Dynamic Motor Analysis - DMA Optimized Motor

JL Audio's proprietary Dynamic Motor Analysis system is a powerful suite of FEA-based modeling systems, first developed by JL Audio in 1997 and refined over the years to scientifically address the issue of speaker motor linearity. This leads to vastly reduced distortion and faithfully reproduced transients... or put simply: tight, clean, articulate bass.

Engineered Lead-Wire System

Carefully engineered lead-wire design and attachments ensure controlled, quiet lead-wire behavior under the most extreme excursion demands.

Managing the lead-wires on a long-excursion woofer is one of the trickier aspects of its mechanical design. To address this, many long-excursion woofers today rely on a simple solution that weaves the lead-wires into the spider (rear suspension) of the driver.

The biggest problem with this approach is that spider limiting behavior plays a hugely important role a woofer's performance. Lead-wires that are attached or woven into the spider material can alter the spider's "stretching" behavior. The tinsel wire naturally has less 'give' than the fabric material of the spider leading to asymmetrical spider behavior and non-uniform stress distribution around the spider circumference. The wire attachment points can also cause localized pulling and tearing forces at the spider's excursion limits. As such, longevity becomes a major concern and makes the woven-in design less than ideal for very long-excursion designs.

While a traditional 'flying lead' design does not compromise spider linearity or radial stability, it creates its own challenges on a long-excursion woofer. Managing the 'whipping' behavior of the wire and making sure it does not contact the cone or spider is one challenge. Another is ensuring that the leads do not short one another or the frame of the woofer.

To overcome these issues, JL Audio's engineered flying lead-wires work in conjunction with carefully engineered entry and exit support structures molded into the terminals and the voice coil collar. Some models also feature jacketed lead-wires to further reduce the likelihood of shorting and fatigue.

The result is flawless high-excursion lead-wire behavior, with outstanding reliability and none of the compromises inherent to a woven-in lead wire system. Building woofers this way requires much more labor and parts complexity than the simpler woven-in approach, but the payoff is in reduced distortion, reduced mechanical noise and improved reliability.

Tab-Ear Frame Design

This frame design feature facilitates mounting the Subwoofer in tight spaces. By employing a tab-ear mounting system, the driver's overall outside dimensions are reduced, permitting it to be mounted in a space that is very similar to that required by the next smaller round woofer frame.

In this example, the “Tab-Ear” frame design allows a 13TW5 13.5-inch driver to fit in a space only slightly larger than a conventional 12-inch woofer requires (only 0.44”. / 11.2 mm bigger).

Concentric Tube Suspension

Our Concentric Tube Suspension™ technology delivers unprecedented excursion in a low-profile woofer.

The biggest challenge in any low-profile woofer design is to create enough mechanical clearance for the speaker to generate enough excursion to meet its output and low-frequency extension goals. Since these goals were very ambitious in the development of JL Audio's low profile woofers, achieving them required development of a new suspension architecture.

JL Audio's solution employs a molded structure which spans over the edge of the motor system, supporting the spider on the outside of the motor's boundaries and the large diameter voice coil on the inside. The large diameter voice coil permits the magnet to sit inside it, rather than surrounding the coil as is typical in most woofers.

The concentric tube structure and the elimination of a conventional top-plate helps us place the motor system higher up into the cone body's space to further compress depth, while still permitting excellent mechanical excursion.

Built-In USA with Global Components

At a time when most audio products are built overseas, JL Audio’s commitment to in-house loudspeaker production continues to grow. To pull this off in a competitive world market, our production engineering team has created one of the world’s most advanced loudspeaker assembly facilities and established a global network of quality component suppliers who build to our specifications. This, combined with our commitment to state-of-the-art assembly technology, allows our skilled workforce to efficiently build JL Audio products to extremely high quality standards, right here in the U.S.A.

Specifications

Power

Continuous Power Handling (RMS)
300W RMS
Recommended Amplifier Power (RMS)
75W - 300W RMS
Nominal Impedance (Znom)

Dimensions

Nominal Diameter
12” / 300 mm
Overall Diameter (A)
12.375” / 314 mm
Mounting Hole Diameter (B)
11.0625” / 281 mm
Bolt Hole Circle Diameter (C)
11.7” / 297 mm
Motor Outer Diameter (D)
5.71” / 145 mm
Mounting Depth (E)
4.62” / 117 mm
Front Grille Protrusion (F)
0.87” / 22 mm
Driver Displacement
0.072 cu ft / 2.04 L
Net Weight
16.5 lb / 7.5 kg

Parameters

Free Air Resonance (Fs)
32.35 Hz
Electrical “Q” (Qes)
0.555
Mechanical “Q” (Qms)
11.066
Total Speaker “Q” (Qts)
0.529
Equivalent Compliance (Vas)
1.189 cu ft / 33.67 L
One-Way Linear Excursion (Xmax)
0.4” / 10 mm
Reference Efficiency (no)
N/A
Efficiency (1 W / 1 m)
85.15 dB SPL
Effective Piston Area (Sd)
67.608 sq in / 0.0436 sq m
DC Resistance (Re)
3.514 Ω

Sealed Enclosure Specifications

Wall Thickness
0.75” / 19 mm
Front Baffle Thickness
0.75” / 19 mm
Volume (net int.)
0.65 cu ft / 18.41 L
External Width (W)
26.5” / 673 mm
External Height (H)
14” / 356 mm
External Depth (D)
5.5” / 140 mm
F3
45.44 Hz
Fc
54.41 Hz
Qtc
0.89

Enclosure Notes

The enclosure recommendations listed above are external dimensions which assume the use of 0.75” (19 mm) thick material. If you are using 0.625” (16 mm) thick material, subtract 0.25” (6.5 mm) from each dimension. Do not use any material with a thickness of less than 0.625” (16 mm) as this may compromise the rigidity of the enclosure.

All enclosure volumes listed above are net internal volumes! Driver displacement, port displacement and brace displacement must be added to obtain the final gross internal volume. All enclosure dimensions above have already taken this into account.

When using multiple subwoofers in a common enclosure you will need to recalculate the enclosure and port dimensions. For assistance please contact your authorized JL Audio dealer or JL Audio Technical Support.

We recommend the use of this speaker in a bi-amplified system using high-quality satellite speakers and a high-quality amplifier. We do not recommend the use of this subwoofer with a passive crossover (coil), as this type of device will adversely affect performance.

All specifications are subject to change without notice.

Safety Notice

Prolonged exposure to sound pressure levels in excess of 100dB can cause permanent hearing loss. This high-performance speaker can exceed this level. Please exercise restraint in its operation in order to preserve your ability to enjoy its fidelity.

When installing a subwoofer in your vehicle, it is extremely important to secure the enclosure firmly. We recommend bolting the enclosure through the metal of the floorpan or the frame of the vehicle with large diameter washers for reinforcement. If an enclosure is not firmly attached, it can become a projectile in a collision. This is particularly important in a hatchback, station wagon, sports utility vehicle, or van.

Ported Enclosure Specifications

Wall Thickness
0.75” / 19 mm
Front Baffle Thickness
0.75” / 19 mm
Volume (net int.)
1.125 cu ft / 31.86 L
External Width (W)
31.75” / 806 mm
External Height (H)
16” / 406 mm
External Depth (D)
7” / 178 mm
Internal Slot Port Width (SW)
5.5” / 140 mm
Internal Slot Port Height (SH)
2.25” / 57 mm
Internal Slot Port Length (SL)
22.625” / 575 mm
Port Extension Length (EL)
20.75” / 527 mm
Tuning Frequency (Fb)
34 Hz
F3
31.79 Hz

Enclosure Notes

The enclosure recommendations listed above are external dimensions which assume the use of 0.75” (19 mm) thick material. If you are using 0.625” (16 mm) thick material, subtract 0.25” (6.5 mm) from each dimension. Do not use any material with a thickness of less than 0.625” (16 mm) as this may compromise the rigidity of the enclosure.

All enclosure volumes listed above are net internal volumes! Driver displacement, port displacement and brace displacement must be added to obtain the final gross internal volume. All enclosure dimensions above have already taken this into account.

When using multiple subwoofers in a common enclosure you will need to recalculate the enclosure and port dimensions. For assistance please contact your authorized JL Audio dealer or JL Audio Technical Support.

We recommend the use of this speaker in a bi-amplified system using high-quality satellite speakers and a high-quality amplifier. We do not recommend the use of this subwoofer with a passive crossover (coil), as this type of device will adversely affect performance.

All specifications are subject to change without notice.

Safety Notice

Prolonged exposure to sound pressure levels in excess of 100dB can cause permanent hearing loss. This high-performance speaker can exceed this level. Please exercise restraint in its operation in order to preserve your ability to enjoy its fidelity.

When installing a subwoofer in your vehicle, it is extremely important to secure the enclosure firmly. We recommend bolting the enclosure through the metal of the floorpan or the frame of the vehicle with large diameter washers for reinforcement. If an enclosure is not firmly attached, it can become a projectile in a collision. This is particularly important in a hatchback, station wagon, sports utility vehicle, or van.

More Information
Brand JL Audio
RMS Power 300W RMS
Nominal Impedance 4 Ω
Shallow Mount Yes
Subwoofer Size 12"
Subwoofer Type Single Voice Coil (SVC)