For a speaker enclosure I'm working on, the main driver's min requirement by the manufacturer is 50W. I had planned for 20. Because of speaker sensitivity, if I wanted to make it 40 (being closer to recommended) I would probably need to add another woofer. Then... well my brain did its brain thing and I thought this up... Two subs iso with the main driver in front. Either do a wave guide and a port, or two sets of 3 PRs. Good idea, or bad idea?