Well, I talked to Jakeman about this once, and read an article on audioholics about setting up multiple subs. Both say to average the distances of your subs. It is best if you can try to space the subs close to the same distance, but that is not always easy.
So following that rule, I have the following:
12ft (350) + 12ft (350#2) + 15ft (EP600 12ft+3ft for the DSP) / 3 = 13ft average.
I plan to experiment later today with just using the actual 12 ft measurment for the 600, and not figuring in the 3ft addition, but probably won't be able to tell the difference.
Again, if you can place all the subs the same distance, you don't have to average.
