This is gonna be major WHUMPazz in a compact package. Just waiting for a few final specs before filling in the blanks. I've got 6 iterations charted and measured. This could actually slim down from 18" to as far to 17" and have phase coherence and near-identical low frequency reponse with the larger version. It stacks with the fEarful 15+6. For standalone use or when using two of them it can be set either way. If building two, the baffle should be mirror-image for best dispersion.