The Model 2451H/J is a 38 mm(1-1/2 in) exit diameter, compact size and light weight addition to JBL’s family of professional quality neodymium compression drivers. The 38 mm exit allows the Coherent Wave™ phasing plug to directly couple with Optimized Aperture™ Bi-Radial® horns to provide lower distortion and better coverage control to 20 kHz than previous designs.
The Coherent Wave™ phasing plug structure has four equal length passages to provide in-phase summation of diaphragm output at the 38 mm exit, This optimized configuration produces coherent acoustical power up to much higher frequencies than more conventional designs.
The diaphragm design includes JBL’s exclusive three-dimensional diamond pattern surround’ tuned to reduce fatigue inducing stresses in the membrane and support structure. This provides predictable normal resonance modes, and radial reinforcing ribs increase diaphragm stiffness. This diaphragm design combined with the Coherent Wave™ phasing plug increases the 2451’s output in the 5 kHz to 20 kHz range.