Wayne Parham Messages: 18791 Registered: January 2001
Illuminati (33rd Degree)
I never made such a thing. But if you take two three π subs and face them together, one with the woofer installed backwards, magnet out, you will have a push-pull sub. Place them close to one another, just to the point where the cone of the forward-facing speaker will not strike the magnet of the other at full excursion. Make your cabinet to position everything that way.