Coaxial Speaker System: 4-inch (100 mm) Woofer, 0.75-inch (19 mm) Aluminum Dome Tweeter

C1 speakers deliver real substance and great audio performance in a format designed for easy fit behind factory grilles.

To facilitate fit, breakaway mounting tabs on the woofer frame allow the C1-400x to be installed in four-hole or two-hole mounting configurations.

C1 woofer drivers benefit from proprietary FEA modeling and JL Audio's expertise in low-frequency driver design. This knowledge is used to create speakers that can play loudly, while maintaining a smooth, dynamic, low distortion sound. At the core of the C1-400x is a proprietary, stamped, steel 4-inch (100 mm) frame and a DMA-optimized motor system. A mineral-filled, injection-molded polypropylene cone is suspended with a rubber surround on the front, and a carefully engineered spider at the top of the voice coil, to precisely control motion and prevent impact between the voice coil and the back plate. Tinsel leads are carefully routed and attached to the spider to prevent fatigue and buzzing. These are the same kinds of features and materials normally found on much more expensive loudspeakers.

Equipped with a true, edge-driven, aluminum dome tweeter, C1 speakers stand further apart from others in its category with superior high-frequency clarity and definition. The tweeter’s design has inherently excellent off-axis response and high-frequency extension. It also benefits from the damping of a silk surround suspension and Ferrofluid in the voice coil gap, along with the superior strength of a neodymium magnet circuit. A true, 2nd order high-pass filter is employed to further enhance smoothness and improve power handling.

Sold as a pair. Grilles not available.

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.

Aluminum Dome Tweeter

Summary:
Lightweight Aluminum Dome tweeters deliver sparkling high-frequency detail that extends well beyond the frequency response of typical human hearing.

Detailed Information:
Compared to similar textile designs, aluminum tweeter diaphragms offer superior stiffness and high-frequency extension, with only a minor penalty in efficiency. JL Audio’s aluminum dome tweeters employ a rubber surround and ferrous fluid in the motor gap to damp the aluminum diaphragm. This additional damping reduces ringing and improves the tweeter’s smoothness of reproduction while still delivering the high-frequency energy and extension that metal domes are known for.