CS212RG-W1v2-2

V-Groove MDF Construction

Summary:
This advanced cabinet-building technique uses CNC-machining to create precise panel joints that make enclosure assembly more efficient and exact.

Detailed Information:
We begin with quality medium-density fiberboard, which is then machined on our CNC-controlled KOMO woodworking stations. These powerful machines are able to cut a wide range of features onto a sheet of MDF, with minimal waste and absolute precision. The KOMO machines cut out the woofer holes, terminal holes, cut dado grooves, create countersinks and most importantly, cut the angles at the edges of the panels that form the enclosure's main shell so that these panels fit together precisely, with no gaps or leaks.

Once the panels are cut, assembly technicians line them up in the correct order and glue their outer faces onto a long piece of carpet, creating a "wrap": a long series of panels, hinged temporarily by the carpet. In the next assembly step, our wood assembly teams fill the V-grooves between the panels and any dado grooves that receive dividers or secondary wraps with wood-glue. Once the glue is applied, the enclosure shells folds together along the V-grooves, capturing dividers in the dado grooves and secondary wraps, and evenly spreading the glue throughout the joints. One line of mechanical fasteners is applied to hold the structure together while the wood glue dries.

The V-groove technique greatly improves assembly efficiency, and also results in a far stronger and better sealed enclosure than the typical butt-joint construction found on imported enclosures. The quality of the MDF used in JL Audio systems is also vastly better than the typical "China-Grade MDF" used in the imported products.

Dynamic Motor Analysis - DMA Optimized Motor

Summary:
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.

Detailed Information:
Since 1997, JL Audio has been at the forefront of Finite Element Analysis-based modeling of loudspeaker motors and suspensions. This research is aimed at decoding what we refer to as the "Loudspeaker Genome"... a project aimed at understanding the true behavior 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 our 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 us a highly accurate model of a speaker's actual behavior 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 analyzed. These modeling routines are intense, requiring hours to run for a whole speaker.

DMA is able to analyze 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 modeling, 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 our engineers arrive at motor solutions that minimize this instability. Analyzing this behavior is critical to understanding the distortion mechanisms of a speaker motor and sheds light on the aspects of motor design that determine truly linear behavior:

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

Our ability to fully analyze these aspects of motor behavior allows our 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.

Elevated Frame Cooling (U.S. Patent #6,219,431 & #6,229,902)

Summary:
JL Audio's patented Elevated Frame Cooling design delivers cool air through slots directly above the top-plate to the voice coil of the speaker. This not only enhances power handling, but also sound quality by minimizing dynamic parameter shifts and power compression.

Detailed Information:
Many speakers employ venting techniques to enhance voice coil cooling. This is typically accomplished by having big holes in the sides of the frame just below the spider attachment shelf. While it provides a modest cooling benefit, this low-velocity air-flow does not blow directly or strongly on the voice coil.

Our patented design improves upon this cooling technique in a number of ways. By elevating the frame above the top-plate of the motor (via stand-offs integrated into the bottom of the frame) a narrow, high-velocity air-path is created between the bottom surface of the frame and the top surface of the top-plate. This air path leads directly to the voice coil and then turns upward into the spider air cavity. By utilizing the pumping action of the spider through this focused air path, a large volume of cool air hits the coil windings directly.

Another important benefit is that the upper surface of the top-plate (one of the speaker's hottest parts) is directly exposed to cooling air flow, whereas on a conventional design it is isolated from the air flow by the lower flange of the frame. The elevated frame technology greatly increases thermal power handling, reduces compression effects and does so without any additional parts.

Floating Cone Attach Method - FCAM™ (U.S. Patent #6,501,844)

Summary:
This assembly technique, conceived by JL Audio, ensures proper surround geometry in the assembled speaker for better excursion control and dynamic voice coil alignment.

Detailed Information:
JL Audio's patented FCAM™ 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.

Vented Reinforcement Collar (U.S. Patent #5,734,734)

Summary:
JL Audio's patented Vented Reinforcement Collar (VRC®) improves the rigidity and stability of the cone/spider/voice coil junction and directs airflow over the voice coil windings for improved thermal performance.

Detailed Information:
The Vented Reinforcement Collar (VRC®) is a composite structure that addresses two issues related to reliability.

By reinforcing the critical junction betweeen the cone, voice coil and spider, the VRC greatly reduces failures due to glue breakdown or material weakness. It does this by greatly increasing adhesive contact area and providing stress relief to the spider material at excursion extremes.

The VRC™ also features slots that facilitate air flow directly onto the voice coil windings. This reduces thermal compression effects and enhances reliability.

Current versions of the VRC™ also incorporate lead-wire strain relief structures to improve mechanical reliability.

Insert Molded Suspension / Coil / Terminal Sub-Assembly (U.S. Patent #7,379,558)

Summary:
Spiders, voice coils, terminals and lead wires are preassembled, using a patent-pending process, onto a composite carrier for improved precision and reliability.

Detailed Information:
A conventional speaker is assembled in layers. In other words, multiple parts are assembled and glued sequentially into the basket, leading to stacking of tolerances and making it difficult to achieve optimal assembly precision.

JL Audio's patent-pending insert-molded spider carrier permanently bonds the spider to a mechanically robust carrier that also incorporates the terminal assembly and lead wire strain relief features for enhanced relability and optimal alignment of parts. This subassembly is assembled outside the speaker basket, for optimum alignment and glue-joint integrity. The benefit is a more precisely built, more mechanically sound loudspeaker.

Customizable Trim Ring (U.S. Patent #D480,709)

Summary:
This removable ring can be painted to match the installation theme and directly receives JL Audio grille mesh inserts (sold separately).

Detailed Information:
This ABS trim ring is molded in black, but that doesn't mean it has to stay that way. By custom painting it, you can match your installation theme and create a personalized look.

Specifically-designed grille mesh inserts are available separately and fit into the inner diameter of the trim ring.

Helpful Tip: Installing the grille mesh inserts is much easier before mounting the woofer into the enclosure.