JL Audio 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 - 6,000 Hz

With 24 dB/octave filters: 400 Hz - 5000 Hz

With 12 dB/octave filters: 500 Hz - 4000 Hz

Built in USA with Global Components

Sold individually, with a cast-alloy grille tray and a specially perforated steel grille insert. 

C7-350cm Specifications

Impedance Speaker Type: Component Midrange

Nominal Diameter: 3.5 in. (90 mm)

Design Bandwidth: 300 Hz - 10 kHz

Nominal Impedance (Znom): 4 ohms

Continuous Power Handling: 100W

Recommended Amplifier Power: 50-150W

Net Weight: 0.71 lbs. (0.32 kg)

Driver Rear Displacement: 0.0024 cu.ft. (0.068 liters)

Min. Recommended Sealed Enclosure: 0.014 cu.ft. (0.4 liters)

Parameters:

Voice Coil Resistance (Re): 3.245 ohms

Free Air Resonance (Fs): 156.9 Hz

Reference Efficiency (no): 0.270%

Efficiency @ 1W/1m: 86.5 dB SPL

Sensitivity @ 2.83V/1m: 89.5 dB SPL

Electrical “Q” (Qes): 0.590

Mechanical “Q” (Qms): 6.454

Total Speaker “Q” (Qts): 0.541

Equivalent Compliance (Vas): 0.015 cu.ft. (0.430 liters)

Moving Mass (Mms): 4.009 g

Mechanical Compliance (Cms): 0.000257 m/N

Magnetic Strength (BL): 4.66 N/A E

ffective Piston Area (Sd): 5.31 sq.in. (0.003426 sq. m)

One-Way Linear Excursion (Xmax): 1 mm