Ok, here is a recap of my posting from 2014.
"For all you DIY’s. I have received many emails to make these items. They are quite simple to make.
I used 1/8" copper caps with a large copper cone from a company called "Hareline" inside. Hareline makes items for fishing lures and can be bought from Amazon.
The caps however, will need to be purchased from a plumbing house. Then just simply glue the cone inside the cap. The cone is a direct drop in. I used Elmer’s school glue to seal the cone inside the cap.
Audio Magic also places a crystal in the middle of there "Bells". I suppose you could use (Blu Tack)to hold a crystal in the cap before gluing the cone in it.
Personally I don’t think its necessary.
When you place the cones (I used blue tack) on the wall or the equipment, place them in the middle first with one at the height of your speaker, then near the floor and perhaps one up high. If you go too high with them it may accent the higher frequencies. But do experiment.
The others were placed at the first and second reflection points on the side walls.
At the wall behind you, I placed them again in the middle, at floor level, mid and high.
Then from there you can experiment through your room and equipment. Some places they worked good and some not so good.
I must add that I also own the SR FEQ unit which is supposed to excite these things.
by ozzy"
ozzy