I've tried everything on my ported box (200L @19hz) to make it sound better. I can't tune it any lower, I've EQ'd it, I've run a FR, I've played with the phase, etc. I loved my .7Q sealed box so I guess I'll go back. BUT... the reason for trying out a ported box was that I wanted more output. Here's what I propose: Keep the 200L box, load another Tempest into the top of the box and run dual sealed. Then scrap the PE250 and run a big yamaha M-70 power amp on it. (~250wp sub)I've got a Merchand black box coming to control phase, gain, rubble filter etc. Will I run into problems with a sub on the bottom and a sub on the top? Should I run one out of phase? Any other problems I may run into with this set-up? Thanks for the help.