JBL 2450J 100w 16ohm 4-inch High-Frequency Compression Driver

The JBL model 2450J is a professional quality, compact size and light weight large-format high-frequency compression driver that incorporates a neodymium rare-earth magnet assembly.

This is a used driver. It has some material stuck to the back that's not easy to scrape off - the reason for only a "Good" condition rating.

Specifications (from JBL):

Throat Diameter: 49 mm (2 in)

Nominal Impedance: 16 ohms

Minimum Impedance: 12 ohms @ kHz 5 DC

Resistance: 8.5 ohms ± 10% @ 25%

Power Capacity¹:

100 W continuous program above 500 Hz

150 W continuous program above 1 kHz

Sensitivity: 111 dB SPL, 1 W @ 1 m on-axis on horn²

118 dB SPL, 1 mW on plane-wave tube³

Nominal Efficiency: 30% (500 Hz to 2.5 kHz)

Frequency Range: 500 Hz to 20 kHz

Recommended Crossover: 500 Hz or higher, 12 dB/octave minimum

Diaphragm: 0.05 mm (0.002 in) pure titanium

Voice Coil Diameter: 100 mm (4 in)

Voice Coil Material: Edgewound aluminum ribbon

Flux Density: 1.9 T (19,000 gauss)

B1 Factor: 18 N/A

Positive voltage to black terminal gives diaphragm motion toward the phasing plug

Dimensions:

167 mm diameter

139 mm depth

Mounting: Four ¼-20 threaded holes, 90° apart on 101.6 mm (4 in) diameter

Net Weight (without shipping materials): 13 lb

¹Continuous program is defined as 3 dB greater than continuous pink noise and is a conservative expression of the transducer’s ability to handle normal speech and music program material. Continuous pink noise power ratings are rested with pink noise input having a 6 dB crest factor, with a high-pass filter set at the specified lower limiting frequency for two hours duration

²Sensitivity measured with 1 W input at 1 m distance on axis from the mouth of a horn with a Q off 3 averaged in the 2 kHz octave band

³As specified by recognized standards organizations, sensitivity is measured with the driver coupled to a terminated tube. The JBL sensitivity rating represents the SPL in a 25 mm (1 in) terminated tube, using a 1 mW input signal (0.126 V into 16 ohms) swept from 500 Hz to 2.5 kHz. The sensitivity rating with a 1 W input would be 30 dB greater.

Included in the pictures is the frequency swept Impedance graph for this particular driver as-is (without an attached horn.)