JL Audio E-Sub E112 Subwoofer

Powered Subwoofer with 12-inch Subwoofer, 1500 watts

Applying a series of our key technologies, E-Sub powered subwoofers deliver exceptional sound quality, power and value in a wide range of demanding applications

E-Sub drivers employ our exclusive DMA technology to optimize the drivers' motor strength, ensuring linear behavior over a very long excursion range. Unlike typical steady-state modeling systems, DMA takes into account the dynamic shifts created by current flow and back EMF under real power conditions, with real program material. The payoff offered by DMA optimization is a driver that faithfully tracks its input signal, at all listening levels, leading to superior bass definition and dynamics.

The extreme mounting depth of the E-Sub driver is very deliberate. It permits wide gaps to exist between the three suspension elements (the rubber surround and the dual spiders), imparting exceptional mechanical stability over the driver's full excursion range. This further improves linearity, reduces distortion and enhances long-term reliability. In a stroke of engineering elegance, the E-Sub’s steel front mounting flange forms the entire front baffle of the finished product, while the driver’s back-plate is threaded and bolted to the rear wall of its enclosure for support.

To power these innovative drivers, we engineered a completely new switching amplifier with a regulated, switching power supply, making its chassis more compact, lightweight and efficient, while still delivering ample, clean power to fully exercise the E-Sub driver's performance envelope.

Conveniently controlled from the E-Sub cabinet’s top panel, the amplifier incorporates studio-grade signal processing to make adjustments a much more enjoyable experience than rear–mounted controls found on most powered subwoofers. An attractive cover hides and protects the controls during normal use.

The feature set has been designed to allow the use of E-Subs in a wide range of applications, from full home theater systems to dedicated two-channel music systems, to desktop audio workstations. Analog inputs are provided for unbalanced line-level signals or speaker level signals. Dedicated line outputs are included to make a bi-amped system arrangement with no additional hardware required. Useful in combating ground-related noise problems, a rear panel switch configures the line level inputs as grounded or isolated.

The E-Sub’s active crossover is a true two-way, 4th order Linkwitz-Riley design, with a low-pass filter feeding the subwoofer's amplifier and a high-pass filtered signal exiting its line outputs. When the on-board crossover is defeated, as is typical in a home theater installation, the line outputs deliver a pass-through, buffered signal identical to its line inputs, easily permitting multiple E-Subs to be interconnected in a ‘daisy-chain' arrangement. Switchable polarity and a fully variable phase control round out the signal processing section. All signal processing is performed in the analog domain, ensuring very low latency in critical applications.

Precision-built in JL Audio's U.S. factory, all E-Sub are individually performance-verified and tested to deliver years of listening enjoyment in your home audio or home theater system.

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 15W3 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.

True 2-Way Crossover

Summary:
Built-in two-way crossover permits easy integration into two channel audio systems.

Detailed Information:
In high-performance audio systems, a crossover's function is to act as a gateway, filtering and directing precise audio signals towards each speaker as appropriate for its driver's particular size. For example, with a conventional two-way home theater or home audio system, the smaller, main stereo speakers are tasked with reproducing the mid to upper frequency ranges, while larger subwoofers are responsible for the lower frequencies.

Designed with system versatility and practicality in mind, the E-Sub's onboard active crossover can be used in two distinct modes.

• When engaged, it send a 24 dB/octave, low-pass signal to the E-Sub's internal amplifier, while also feeding an alternate 24 dB/octave, high-pass signal to the "Line Outputs" located on the E-Sub's rear connection panel. The result is a true, two-way, 24 dB/octave, Linkwitz-Riley crossover configuration between the E-Sub and the main stereo speakers, without requiring an additional, external crossover.

• When the E-Sub's crossover is not in use, its "Line Outputs" will deliver a buffered, pass-0through signal that is identical to the signal feeding its "Line Inputs". This application is beneficial in multi subwoofer installations to pass a receiver/pre-pro's subwoofer signal from one E-Sub to additional E-Subs.

Vented Reinforcement Collar

Summary:
JL Audio's 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 between 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.

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.

Engineered Lead-Wire System (U.S. Patent #7,356,157)

Summary:
Carefully engineered lead-wire design and attachments ensure controlled, quiet lead-wire behavior 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 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.

Built in U.S.A. with Global Components

Summary:
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. 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.

Since most of our premium loudspeakers incorporate proprietary, patented technologies requiring specific assembly techniques, we find it is vital that the people who designed them have close access to the people manufacturing them. The following JL Audio products are built in our Miramar, Florida factory, with global components:

• Subwoofers: W7, W6v3, TW5v2, TW3, TW1, W3v3
  
• Enclosed Car Subwoofers: Stealthbox®, PowerWedge™, ProWedge™, H.O. Wedge™ & MicroSub™ Enclosed Subwoofers
• Marine Loudspeakers, Marine Subwoofers and Marine Enclosed Loudspeakers
• Home Subwoofers: Dominion™, E-Sub, Fathom® and Gotham®