4412A and 4410A crossovers...how different are they?

[Gino]

I recently bought a few pairs of 4412A's and I noticed one has a burned out crossover network. (74853) I've heard that the 4410A and 4412A use the same network and I've noticed the crossover actually has two part numbers (74852 for the 4410A and 74853 for the 4412A) on it with the appropriate number "blacked-out" with a marker depending on which model it was installed. They must be differently wired depending on which speaker they're installed hence the two part numbers. My questions is if I can only find a 74852, can I use it a 4412A and how do I set it up? I just don't want to fry anything. Thanks in advance, Gino

[Don C]

I recently bought a few pairs of 4412A's and I noticed one has a burned out crossover network. (74853) I've heard that the 4410A and 4412A use the same network and I've noticed the crossover actually has two part numbers (74852 for the 4410A and 74853 for the 4412A) on it with the appropriate number "blacked-out" with a marker depending on which model it was installed. They must be differently wired depending on which speaker they're installed hence the two part numbers. My questions is if I can only find a 74852, can I use it a 4412A and how do I set it up? I just don't want to fry anything. Thanks in advance, Gino

Here are the schematics:
http://www.jblproservice.com/navigat...chematics.html
At a glance, it looks like you would need to remove a jumper and install R6, and replace R3 and R4. But don't take my word, print the schematics and take a close look yourself.