JL Audio C3-570 5 x 7 / 6 x 8" 2-Way Convertible Component

Summary

There are times when an installation calls for a separate woofer and tweeter and other times when a coaxial is the better approach. With the Evolution® C3 Convertible Component Systems, the same product can be deployed in either configuration, delivering outstanding audio power and quality in each application.

Many people mistakenly believe that an oval speaker cannot perform as well as a round one, leading to many instances of 5.25-inch speakers being installed into 5 x 7-inch openings. JL Audio has put in the engineering time and effort to create fantastic-sounding speakers that drop into oval openings and deliver equivalent performance to our 6.5-inch (165 mm) round speaker systems... guaranteed. So, don't make the mistake of losing cone area and efficiency by stepping down to a smaller round speaker... these ovals are as impressive as our round format systems.

The C3-570 system features 5 x 7 / 6 x 8-inch (125 x 180 mm) component woofers with oversized 1.2-inch (30.5 mm) voice coils, mineral-filled polypropylene cones and injection-molded polymer baskets. The woofer design benefits from JL Audio's vast woofer design experience and advanced modeling systems.

The C3 tweeters are built with 1-inch silk dome diaphragms that deliver powerful, extended response, on and off axis. Flush-mounting and surface-mounting fixtures are included to fit a wide variety of installation needs. They can also be mounted onto the woofers in a coaxial format using the included fixtures.

C3 crossover networks are compact and built with premium component parts, including Mylar® capacitors and segmented air-core inductors. Four levels of tweeter attenuation are provided, as well as three levels of mid-range presence adjustment, for twelve possible voicing combinations!

Woofer grilles are not available for this product.

Sonic character: Clean and Powerful

Sold as a pair.

Overview

Convertible Drivers: Coaxial or Component

Summary:
Sometimes a coaxial is the best solution... and sometimes you need to mount the tweeter separately. It's great to have complete flexibility.

Detailed Information:
Coaxial or Component: Both approaches can yield excellent results.

Coaxial mounting has the benefit of placing the tweeter in close proximity to the acoustic center of the woofer, resulting in more coherent output and predictable crossover behavior. From a purely practical perspective, it also avoids having to cut a separate hole for the tweeter.

Separate mounting has the benefit of placing the tweeter where it is less likely to be blocked by legs or other obstructions. As long as you don't separate the tweeter too far from the woofer, this approach will still yield good coherence and predictable crossover behavior.

JL Audio's Convertible Components give you the option of installing the speakers as separate components or as coaxial systems (tweeters mounted onto the center of each woofer). In coaxial mode, the tweeter installs onto a post that attaches to the top of the pole piece with a bayonet-mount mechanism. Short leads are used to connect the tweeter to dedicated terminals on the pole piece (see figures A-D). In separate component mode, a phase plug installs onto the pole piece via the bayonet-mount mechanism (see figures A & F), and the tweeter can be installed with the supplied flush-mount or surface-mount fixtures.

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.

ΩDMA 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 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

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.

Silk Dome Tweeter

Summary:
Light, fast moving silk dome material promotes high-frequency accuracy. 

Detailed Information:
Silk is a natural material with inherently good characteristics as a tweeter diaphragm. In addition to being very light in weight, silk exhibits excellent damping properties, which reduces ringing and resonances in the tweeter’s passband, leading to a smooth, pleasing high-frequency character free from unnatural sibilance or exaggerated brightness. Compared to a harder material dome, a silk tweeter does not exhibit as much ultra-high frequency extension, but is preferred by many audiophiles for its overall balance.

Specifications

General Specifications

• Continuous Power Handling (RMS) 75 W
• Peak Music Power 225 W
• Recommended RMS Amplifier Power (per Ch.) 25 - 150 W
• System Efficiency 90.0 dB @ 1 W / 1 m
• System Nominal Impedance 4 Ω
• System Frequency Response 48 Hz - 25 KHz ± 3 dB

Woofer Physical Specifications

• Frame Outer Diameter* (A) 5.52 x 7.68 in / 140 x 195 mm
• Grille Tray Outer Diameter (B) N/A
• Rear Cover Outer Diameter (C) 4.08 in / 104 mm
• Frontal Coaxial Tweeter Protrusion** (D) 0.78 in / 20 mm
• Frontal Grille Protrusion (E) N/A
• Mounting Hole Diameter (F) N/A
• Mounting Depth (G) 2.52 in / 64 mm

Tweeter Physical Specifications

• Flush Mount Fixture Diameter (A1) 2.12 in / 54 mm
• Surface Mount Fixture Diameter (A2) 1.93 in / 49 mm
• Flush Mount Mounting Hole Diameter (B) 1.875 in / 48 mm
• Flush Mount Fixture Mounting Depth (C) 0.71 in / 18 mm
• Flush Mount Tweeter Frontal Protrusion (D1) 0.32 in / 8 mm
• Surface Mount Tweeter Frontal Protrusion (D2) 0.95 in / 24 mm

Crossover Physical Specifications

• Width (W) 3.36 in / 85 mm
• Height (H) 1.44 in / 37 mm
• Depth (D) 4.72 in / 120 mm

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