DMA is JL Audio’s proprietary Dynamic Motor Analysis system aimed at improving dynamic motor behaviour. As a result of DMA optimisation, JL Audio’s loudspeaker’s motor systems remain linear in force over an extreme range of excursion while maintaining a highly stable fixed magnetic field over a wide power range. This leads to vastly reduced distortion and accurate transient performance….or put simply: tight, clean, articulate bass. Detailed Information.

Since 1997, JL Audio has been at the forefront of Finite Element Analysis-based modelling of loudspeaker motors and suspensions. This research is aimed at decoding what JL Audio refer to as the "Loudspeaker Genome"... a project aimed at understanding the true behaviour of loudspeakers under power and in motion. A major component of this integrated system is DMA (Dynamic Motor Analysis). Starting with the 15W3v3 and the W7 Subwoofers in the late 1990's and early 2000's, DMA has played an important role in the design of all JL Audio woofers sold today, including JL Audio’s component woofers.

DMA is a Finite Element Analysis (FEA)-based system, meaning that it takes a large, complex problem, breaks it down into small solution elements for analysis and then assembles the data to form an accurate, "big-picture" solution. DMA's breakthrough is that it actually considers the effects of power through the coil as well as coil/cone position within the framework of a time-domain analysis. This gives JL Audio a highly accurate model of a speaker's actual behaviour under real power, something that the traditional Thiele-Small models or other low power measurements cannot do. Because DMA does not rely on a steady-state model, it is able to consider shifts in the circuit elements being analysed. These modelling routines are intense, requiring hours to run for a whole speaker.

DMA is able to analyse the real effects of fluctuating power and excursion upon the magnetic circuit of the motor, specifically the dynamic variations of the "fixed" magnetic field. This delivers intensely valuable information compared to traditional modelling, which assumes that the "fixed" field produced in the air gap by the magnet and the motor plates is unchanging. DMA not only shows that this "fixed" field changes in reaction to the magnetic field created by current flowing through the voice coil, but it helps JL Audio’s engineers arrive at motor solutions that minimise this instability. Analysing this behaviour is critical to understanding the distortion mechanisms of a speaker motor and sheds light on the aspects of motor design that determine truly linear behaviour:

• Linear motor force over the speaker's operational excursion range
• Consistent motor force with both positive and negative current through the coil
• Consistent motor force at varying applied power levels

JL Audio’s ability to fully analyse these aspects of motor behaviour allows JL Audio’s transducer engineers to make critical adjustments to motor designs that result in extremely linear, highly stable dynamic loudspeaker motor systems.

The payoff is reduced distortion, improved transient performance and stellar sound quality. Summary Information

This assembly technique ensures proper surround geometry in the assembled speaker for better excursion control and dynamic voice coil alignment. Detailed Information.

JL Audio's patented FCAM^TM technology is an innovative method of bonding the surround/cone assembly to the voice coil former/spider assembly. This feature helps ensure concentricity of the surround, spider and voice coil without torquing the suspension to achieve it. This allows for the inevitable, slight variations in production part dimensions without having them negatively impact the integrity of the suspension and coil-centering at high excursions. Summary Information

JL Audio’s patented Concentric Tube Suspension™ technology delivers unprecedented excursion in a low-profile woofer. Detailed Information.

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 patented solution employs a moulded 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.Summary Information

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

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 behaviour 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" behaviour. The tinsel wire naturally has less 'give' than the fabric material of the spider leading to asymmetrical spider behaviour and non-uniform stress distribution around the spider circumference. The wire attachment points can also cause localised 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' behaviour 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 moulded 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 behaviour, with outstanding reliability and none of the compromises inherent to a woven-in lead wire system. Building woofers this way requires much more labour and parts complexity than the simpler woven-in approach, but the payoff is in reduced distortion, reduced mechanical noise and improved reliability.
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JL Audio's Miramar, Florida loudspeaker production facility is one of the most advanced in the world.
Detailed Information.

At a time when most audio products are built overseas, JL Audio’s commitment to in-house loudspeaker production continues to grow. All W7’s, W6’s, TW5’s, TW3's, W3v3’s and some of JL Audio’s ZR products. JL Audio also build their Marine Speaker Systems, Home Subwoofers, Stealthbox^® products and the vast majority of their enclosed subwoofer systems in Florida.

To pull this off in a competitive world market, JL Audio’s production engineering team has created one of the world’s most advanced loudspeaker assembly facilities. This commitment to state-of-the-art technology allows JL Audio’s highly skilled workforce to efficiently build JL Audio products to extremely high quality standards.

While it is also feasible to build good quality products overseas (and JL Audio do build some of their products in Europe and Asia), it can be challenging when the product’s technology is innovative or complex. Since most of JL Audio’s premium loudspeakers incorporate proprietary, patented technologies requiring specific assembly techniques, JL Audio prefer that the people who design them have close access to the people manufacturing them. Summary Information

Murphy’s law of low-frequency acoustics prescribes that a subwoofer will generally sound best in the most impractical spot in the room… a fact that home theater and audio enthusiasts battle constantly. Subwoofer placement almost always involves a compromise between sonic performance, practicality and aesthetics.

To face this dilemma head on, JL Audio subwoofer systems incorporate a clever piece of technology called Digital Automatic Room Optimisation (D.A.R.O.).

The D.A.R.O. system self-generates a series of calibration tones, measures the response at the listening position and automatically configures an 18-band, 1/6 octave equalizer for a flat end-result.

The system effectively allows for smooth, well balanced sub-bass from a variety of locations that may have been less than ideal without D.A.R.O.

To accomplish this complex feat, all you have to do is:

• Connect the included calibration microphone to the front panel of the subwoofer.
• Press the “calibrate” button on the front panel of the subwoofer system.
• Hold the microphone at the primary listening position
• A few minutes later, you have completed this one-time setup routine.

You won’t need a computer or any other external equipment, and you won’t need to navigate and manipulate complex interfaces… D.A.R.O is a fine example of technology in the service of man, if there was one.

This proprietary, discrete control circuit design allows our Class D switching amplifiers to maintain an excellent damping factor for improved transient behaviour and fidelity.

Detailed Information

While Class D amplifiers are well known for outstanding efficiency, they have also been known for less than spectacular sound quality due to weak damping of the driven load and poor power regulation. These factors are critical to subwoofer fidelity as they relate directly to the amplifier's ability to control the motion of the speakers.

JL Audio's Patented Class D output circuit utilizes a discrete control section and a unique feedback loop design that results in outstanding power regulation with a damping factor that's vastly higher than other Class D designs and also higher than most Class A/B amplifiers. The benefit of this exclusive JL Audio technology is tight, clean bass reproduction with the efficiency advantage of Class D.

It is a package tailor-made for world-class bass performance. Summary Information