Wayne Parham Messages: 18752 Registered: January 2001
Illuminati (33rd Degree)
That's right. Cut a piece of insulation the same size as the sheet that lines the top of the box. Then run a bead of white glue along the brace between woofer and tweeter. Set the insulation on that brace, with the front edge resting on the woofer frame, and drop a few dabs of white glue where the cross-section sheet and the back sheet meet. That will hold it in place nicely.
The end result creates two chambers separating the woofer and port. Bass will pass right through but midrange is highly attenuated.