This speaker project is for a friend who likes OB's. And the speakers must fit into his Audi for transporting (rear seats folded forward, speakers occupying trunk & rear passenger compartment). Thus; some compromises are required.
We settled on a modified H-baffle design with an electrically segmented wire-stator ESL panel, 66"H x 14.5"W x 15" base. The triangular base forms the H-baffle and is removable.
The drawing below shows the speaker with a Peerless SLS 12 woofer, front-mounted on the baffle, which was the initial plan. However, we have changed to a different woofer and mounting it on the rear of the baffle.
This will not be a stand-alone speaker-- a single 12 woofer on a baffle this narrow will not give thundering low bass. With that in mind, we opted to break the rules for OB and go with a low-Q woofer for optimal blending to the stat panel (Eminence Kappalite 3012LF). The woofer will only provide mid bass here. The lows will be handled by separate OB subs (each with two 15" AE's).
The panel is tried and true. The rest we won't know until we hear it play.