6 driver cube, locked at centre.

[phase_accurate]

Dave was right, the LTF circuit is somehow restricted in it's possibilities. It can't handle all possible driver/box combinations simply because it can't produce the necessary LTF.
A more refined circuit has been posted on this forum by some Dutch or Scandinavian guy. He called it "biquad". That one would be more flexible.

You have to keep in mind that the higher the peak at fs, the sharper it gets, which in turn asks for more accurate component values.

Regards

Charles

 

[Circlotron]

What type of sub would this (six-driver cube) be called? Would it still be a monopole because the drivers move in and out at the same time? Would there be strange or unpredictable cancellation effects drom the different positions of the drivers?

I expect it would more closely approximate a point-source than a normal single driver setup. I supposse it would be better behaved in some respects. Of course, whether a point-source actually matters at low frequencies is another matter.