I followed Larry's paper to modify the crossover. I bought all the parts for the crossover from Madisound with a total cost of approximately $50. Since Larry handled all the technical stuff, I will describe the more mundane process of performing the modification.
First, I removed the front panel of the speaker. I disassembled the top of the speaker trying to figure out how to get into it. Pretty big brain fart on my part. Everything can be done by removing the front panel and the terminal cup. There are four screws that hold on the front panel which can be accessed by removing the plastic grill inserts on the front of the speaker.
Remove the four screws (shown above) and gently pry off (with your fingers) the front baffle. Try not to damage the seal in the process. Cut off the wires to the woofer and trash them (spade plugs are garbage, IMHO). Cut off the wires going to the tweeter as close as possible to the terminal contacts. Remove the terminal cup from the speaker and unsolder all the wires and clean everything up.
The stock capacitor and the inductor appear to be epoxied to the cup, so I just tried as best as possible to get them out of the way (I actually glued the loose inductor wire down). Screw the cup back into the speaker. I used Mortite weather strip to seal it (pretty much overkill). I ripped out the two foam blocks glued to the inside of the speaker. I needed this area to mount crossover components.
Next, I glued (using Liquid Nails) and soldered in all the new crossover components. While waiting on the glue to dry in the different orientations, these speakers took two or three days to finish. Remember to plan carefully the location of your inductors (space them as far apart as possible and orient them so they don't magnetically couple). I also put some glue inside the front baffle to increase the strength and (hopefully) decrease resonances.
After the crossover was complete, I cut felt and glued it to all non-covered internal surfaces. This did not seem to really help the cabinets damping. Using the finger thump test, the sides ring pretty bad. Gluing the inductor to the one side wall helped more than anything else to reduce the ringing (in that side wall only). I guess I could have followed that trend and glued some pieces of wood (or something else) to the inside wall, but I didn't.
I let everything air for a day after I finished to get rid of as much glue smell as possible. Next, I plugged the two ports on the front baffle with corks. I bought the corks at a local hobby and craft supply store. I wish I would have used black marker to mask the side of the cork which you can see though the port. If I ever take them apart again, I will probably do this. Finally, I stuffed them tightly with polyester fiber fill (a.k.a.-pillow stuffing) and carefully screwed the front baffle back on.
All done!
Last revised: August 12, 1999
