Similar to 2344A, 12" square 100° x 100° PT waveguide incorporates engineered throat constriction, shown in front and rear views, below. I haven't again come across the Tech Note that says why yet, but it matters.
JBL logo and beamwidth specifications are embossed on the face.
While the depth of the horns are nearly identical, the complete assembly with 2431H mounted is significantly less than original 2425H on 2344 left, below. Clearly, the time alignment will be different. I don't know where to measure how much, though. The front plates?
[Me go listen now....]
Preliminary report: These things work plenty good....
