A JBL 4412 looks a lot like this --- the midrange speaker is the middle item on the left.
Changing a JBL midrange speaker is more often a matter of finding a replacement component than actually installing it. The installation on most any JBL speaker is a straightforward removal of screws. Depending on the age of the JBL speaker model, the midrange driver may not have been made for decades. eBay is a proven source for finding those old pristine JBL midranges and tweeters, however, and at prices far less than a new replacement speaker would have cost when they were new.
Instructions
1. Determine if your JBL midrange speaker needs replacement. Non-operation is noticeable, but it can be just a question of a loose wire. Remove the screws with the screwdriver that secure the midrange speaker to the cabinet in a three-way speaker design. Check the wire contacts at the back of the speaker, and disconnect them.
2. Swap this speaker with an operating midrange speaker of a matching pair. If the new midrange works, the first removed midrange speaker must be replaced.
3. Look on the back of the speaker for the model number. JBL printed these numbers on the back of the magnet.
4. Search eBay for the replacement model number of your midrange speaker.
5. Buy one or even a pair of replacement midrange drivers, to have a backup if any other midrange speaker should fail. Usually, you can replacement speakers that are like new. Be sure the eBay seller guarantees the component will not be DOA (dead on arrival).
6. Install the new midrange driver in the JBL cabinet, reversing the steps taken to remove the old one.
Tags: midrange speaker, your midrange speaker, back speaker, midrange driver, model number