[brent_s]

Someone either at the Cult or HTGuide tried this. I haven't seen the thread recently, but last I recall he was having major problems getting an air tight seal between the baffle and brick surround.

And as Nathan says, there's a potential issue with the driver seeing the flue as a port or transmission line, depending on cross sectional area. Instinctively, I would think the flue area should approximate the Sd of the driver(s) chosen to avoid semi pressurizing the firebox and creating a lossy ported box.

How big is the firebox? Assuming you can overcome the baffle to brick sealing issue, you might could create a sealed or ported alignment by plugging the flue. Just a thought.

-Brent