thanks for your advice, I am pretty much convinced...less than $50 for the plans so I am not in too deep...I guess you really would not like the cornu spiral horn then...has 4 nautilus style spiral chambers eminating from the backloading cavity...I have already begun work on this and perhaps I am screwed I have Fostex sigma 208 full-range drivers waiting to go into this...oh well, live and learn...tony