Jbl 2405 h brochure

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b, 2405H Ultra-High Frequency Transducer better temperature stability, resistance to demagnetiza- tion, reduction in weight over typical ferrite material, and give the highest performance on an actual production basis. By precise machining, a flux density of 1.75 tesla (17,500 gauss) in the voice coil gap is realized. The diffraction horn assembly is die cast of solid aluminum. Internally, the annular voice coil diaphragm is pneumatically formed of fatigue-resistant aluminum alloy. Wire used in the 44 mm (13/4 in) voice coil is aluminum, milled to a thin ribbon. This process places a maximum amount of conductor in the magnetic gap for optimum efficiency and transient response. The use of high-temperature voice-coil former materials and adhesives has improved the power handling and rug- gedness of the driver. The voice coil itself is identical to the previous alnico magnet model, so that impedance and network matching will be the same. Architectural Specifications: The transducer shall have a maximum diameter of 98 mm (3/8 m) and a depth of 83 mm (3% in) and weigh not less than 2.3 kg (5 lb). The dlffraction horn shall be die cast of aluminum and the magnetic circuit will weigh not less than 1 8 kg (4 lb ). Voice co11 diameter shall be 44 mm (1% in), operatmg m a magnetic field whose flux density measures at least 1.75 T (17,500 gauss). Voice coil wire shall be milled alummum ribbon The transducer shall have a measured sensltlvity (SPL at 1 m (3.3 ft) with a 1 W input, swept from 7 kHz to 20 kHz) of at least 105 dB on axls On-axls frequency response measured under free field condo- tions at a distance of 18 meters (6 ft) or more shall extend from 7 kHz to 20 kHz within plus or minus 3 dB. Horizontal dispersion shall be uniform at 45 degrees off-axls at 16 kHz and 30 degrees off-axis at 20 kHz, when measured at the 6 dB down pomts relative to on-axls fre- quency response characteristics using %-octave band pink noise as the slgnal source Nominal Impedance shall be 8 ohms and power capactty shall be at least 20 watts when driven by pink noise, band-limited from 6 kHz to 20 kHz. The transducer shall be JBL Model 2405H r 200 180 100 8: 70 60 SO 40 30 / I , I 20 I I I I I I I Beamwidth vs. Frequency 10 I 2 3 5 10 20 Frequency, kHz Vertical dispersion of the 2405H. T I j__- -l-L Polar response of the 2405H in the horizontal plane, measured with %-octave band pink noise in a free-field environment. JBL Professional 8500 Balboa Boulevard, PO. Box 2200 Northridge, California 91329 U.S.A. H A Harman International Company W9110M P1058