B&w *01 Midranges

Am hoping anybody know the differences between the midranges between the 801#2 vs 801#3 ?

wondering if the drivers are compatible with one in other


#1 #3??? Do you mean D (original) vs. D3? The current version of 8 series of B&W is the D4

Matrix 801 Series 2 is a part number  Mr-100

Matrix 801 Series 3 is a part number  ZZ00558

Series 3 did away with the protection Circuit in the crossover.

I am Rebuilding a 800 matrix Pair