Dear Antone,
Your suggestion would be ok if the boxes are the same, but the bottom ones are subs with RCF 18" woofers (25-120Hz)and above them are the bass cabinets with Eminence 15" speakers (120-440Hz).
Maybe it would be good to rotate every other box for 90 degrees clockwise and counterclockwise so every two boxes in the same range would make one horn. I'll try it on the next gig. But I'll change the whole configuration soon. I"ll put the 18"s in 2 double boxes per side and put the 15" from the tops into this sub boxes so that will make 16 bass cabinets and 4 double subs in total. And for the tops, I'll put one 12" or two 10" per box.
But thank for the advice.
Vladimir