i love 4th orders on low power systrems, but with yours a regular ported box tuned low would be smaller and give same output. to me 4th order advantages are on low power systems, so ifyou got 500 rms or less and the room, do the bandpass. good luck
I've had dozens of ported setups and looking to do something different. I tried 35hz tuning in winisd and it looks like it looses way too much in the high end. Now I'm thinking 8 ported @ 43hz and 4 sealed. Ported with (4) 6" aeroports which could be left full length... is this going to be loud/low and not too much airspace for the woofers?