As I contemplate taking my midrange driver down 6dB to match the BR-loaded woofer, I must admit I'm think about what a cornerhorn implementation would do for the 1620's efficiency, leaving the 2123 facing forward, as was done in the 18" cornerhorn Bill posted pix of a few weeks or a month back.How many dB would that buy me back? As a SET guy, I find throwing away efficiency painful in the extreme!
Keep your ears and your mind open.