As I understand it (not that that means much

The 2 schools of thought......Say we have a 1' diameter baffle:

1) the circumferance must = 1wl so.....
cir = pi * dia = pi
Fc = 1130 / pi = 360Hz

2) the distance front to rear of driver must = wl/2 so
Fc = 1130 / (2*dia) = 565Hz

#1 is certainly more attractive and seems to work, but what about the 'rear wave cancellation' of #2. ???????????