Wayne Parham Messages: 18787 Registered: January 2001
Illuminati (33rd Degree)
If you were to run the exact same cabinet as the three π loudspeaker, with the midwoofer and port in the same positions, I would not expect you to have any problems with standing wave harmonics mucking up the midrange. That's a design that has been tested extensively.
Putting a 15" woofer in there makes it a little different though, in that the midwoofer is larger. But I think the standing waves would line up pretty much the same, and the pressure and zero nodes would be in the same places. So that's a pretty good way to go.
The thing is, I think that cabinet may be a little small for your woofer in terms of damping. You won't have standing wave problems, but you may have more traditional T/S alignment problems. That part is easy enough to check with garden variety T/S simulators though.