I have a set of 4Pis with DE250 and have just ordered a pair of H290C waveguides from you. I understand there is a change in the crossovers. Would you email me the crossover diagram with the changes I should make?
The change from 20uF to 10uF in position C4 slightly shifts the forward lobe so that it is more centered vertically. When C4 is 20uF, the vertical nulls are located 15° above and 25° below the center of the baffle normal. So the forward lobe is oriented slightly downward. When C4 is 10uF, the forward lobe is centered, with vertical nulls spaced +/-20° above and below the centerline.
The resistor in position Rs should be a 10 watt part. It is required for the H290C waveguide, so please install it when you mount your new waveguides.