JL Audio C7-350CM - 9cm Compo-Mitteltöner

C7-350cm
3.5-inch (90 mm) Component Midrange, with Grille

• C7 is the pinnacle of JL Audio automotive loudspeaker design, benefiting from our most advanced development tools and a complete commitment to precision manufacturing.
• The C7-350cm component midrange is designed to operate in a 3-way system, with a woofer and tweeter. Conceived and purpose-built from the ground up, it offers exceptional transient response and outstanding linearity, resulting in unsurpassed clarity and natural mid-range reproduction. Distortion and non-linearities have been minimized through critical optimization of dynamic motor and suspension behaviors.
• Passive crossover networks are not included with C7 drivers, as they are designed for active systems. Instead, we recommend a high-quality tuning DSP, such as the JL Audio TwK 88 or D8, and a dedicated amplifier channel for each C7 loudspeaker in the system. Precise setup of equalization, delay and crossover filters will ensure optimal in-vehicle performance.
• C7-350cm Design Notes:
• Cone and Dust Cap: Vacuum-formed, mineral-filled polypropylene material offers excellent damping and low mass. The cone body features a gentle curvilinear profile to optimize response. A concave dust cap further improves high frequency behavior.
• Suspension design: The moving assembly is suspended and damped via a linear profile spider formed from a Nomex/polycotton blend, and a positive-roll, rubber surround. The two combine to provide optimum damping without prematurely restricting excursion.
• Motor Design: The C7-350cm employs a high-density magnetic circuit with a high-grade, neodymium magnet, and a specially machined, U-Yoke motor topology. Motor magnetics have been precisely optimized utilizing advanced FEA tools to reduce distortion and provide linear motor force throughout the driver's performance range.
• A 36 mm (1.42 inch) diameter, overhung voice coil is employed, wound with copper-clad aluminum wire onto a fiberglass voice coil former. The oversized voice coil offers extended power handling capability, minimizing thermal compression and distortion at higher listening levels.
• Chassis Design: A purpose-engineered cast alloy basket is employed, featuring thin spokes to maximize rear open area.
• Design Bandwidth:
• With 48 dB/octave filters: 300 Hz - 10 kHz
• With 24 dB/octave filters: 400 Hz - 10 kHz
• With 12 dB/octave filters: 500 Hz - 10 kHz
• Built in USA with Global Components
• Sold individually, with a cast-alloy grille tray, one fine mesh steel grille insert and one spiral steel grille insert.
• The performance of every C7 driver is tested and verified, then assigned a unique serial number. Register your C7 loudspeaker online to receive a copy of its specific Acoustical Test Report: https://c7.jlaudio.com/index.aspx

General Specifications

• Continuous Power Handling (RMS): 100 W
• Peak Music Power: 200 W
• Recommended Amplifier Power (RMS): 50 - 150 W / Ch.
• Nominal Impedance: 4 ohms
• Frequency Response: 300 Hz - 10 KHz ± 3 dB

Parameters

• One Way Linear Excursion (Xmax): 1 mm
• Moving Mass (Mms): 4.009 g
• Reference Efficiency (no): 0.27%
• Sensitivity: 89.5 dB at 2.83V / 1m
• Voice Coil Resistance (Re): 3.245 ohms
• Total Speaker “Q” (Qts): 0.541
• Mechanical Compliance (Cms): 0.000257 m/N
• Mechanical “Q” (Qms): 6.454
• Electrical “Q” (Qes): 0.59
• Efficiency: 86.5 dB at 1W / 1m
•                  92.5 dB at 1W / 0.5m
• Equivalent Compliance (Vas): 0.015 cu. ft. (0.430 liters)
• Free Air Resonance (Fs): 156.9 Hz
• Magnetic Strength (BL): 4.66 N/A
• Effective Piston Area (Sd): 5.31 sq. in. (0.003426 sq. m)

Midrange Physical Specifications (Pict.6)

• Frame Outer Diameter (A): 3.45 in / 88 mm
• Bolt Hole Circle Diameter (B): 3.15 in / 80 mm
• Mounting Hole Diameter (C): 2.87 in / 73 mm
• Grille Tray Outer Diameter (D): 3.95 in / 100 mm
• Frontal Grille Protrusion (E): 0.58 in / 15 mm
• Mounting Depth (F): 1.46 in / 37 mm
• Motor Outer Diameter (G): 2.36 in / 60 mm