The model 2426H is a professional quality high frequency compression driver which incorporates JBL’s titanium diamond diaphragm. This titanium diamond structure combines the ruggedness of phenolic and composite-type diaphragms with the outstanding frequency response of fragile aluminum and exotic metal diaphragms.
JBL’s exclusive suspension1, consisting of a three-dimensional diamond pattern, reduces bending stresses in the diaphragm support structure. The depth of the diamond pattern is closely controlled to provide predictable frequencies for the 2nd and 3rd normal resonance modes and for the basic suspension resonance.
The mathematically determined phasing plug consists of concentric exponential horns to minimize phase cancellations. Phasing plug, throat exit tube and diaphragm assemblies are identical to the previous model.
All cast parts and tolerances are held to the same levels traditionally associated with JBL designs. Additionally the press-fit assembly and interlocking parts assure greater resistance to the mechanical shock. Diaphragm assemblies are rim centered rather than pin mounted, for instant interchangeability and ease of field service. Mounting is provided for standard 25 mm (1 in) three bolt pattern. The front snout may be removed (unscrewed) to allow standard 1 3/8” -18 screw mounting. Through holes for external attachment points are also provided. A machined ring of copper surrounds the pole piece to counteract the inductance of the voice coi1 at high frequencies. After manufacture, the frequency response of each driver is tested for conformity to rigid performance standards. The 2426H is offered in an 8 ohm impedance, and the otherwise identical 2426J is offered in a 16 ohm impedance.