My HT room is 20' x 15', with 12' ceilings, and one 20' side opens completely to a kitchen and breakfast area with 12' ceilings. I have a lot of room to fill with bass!! I want to build a SWer that combines both tight bass for music and OOMPH for home theatre. I have been considering the 12" SHIVA or 15" TEMPEST, built in one of Adire's standard alignments. The biggest constraint to this project is the SAF. I can't build anything higher than 30", which rules out some of the vented Tempest designs that Adire had suggested to me. Does anyone here help me decide on which (1) driver and (2) subsequent Adire alignment would work best for my room and SAF criteria? (e.g., vented SHIVA vs sealed TEMPEST). This is my first crack at DIY, so while a sealed design would be easier to build, I would try a vented design if needed. Thanks.