In the autumn of 2005, just on a whim, I listened to the CSS FR125S (on the right) simply mounted on a board. I was shocked at how much better they sounded than when boxed in, having tried them in several boxes. Then I tried the Visaton B200 (center), which is a driver purposefully designed for an open baffle mounting. Then I tried the Fostex F200a (left); liking this driver with a foam grill to tame the treble.
With these drivers, I've played with boards leaned upon boards, boards puttied to boards. It seems even an inch of board here or there made a difference. Any board seemed to restrict the sound and soon, I was wishing bass could be gotten from a driver on a stick (like a lolipop).   Anyways, I've no perference for any shape. I do like the winged method because it helps the bass without making a cabinet too imposing in my small listening room. 

The cabinet on the left is plywood with cork and some felt. There is also a solid piece of Ash beneath the driver, which I believ helps channel vibrations to ground. The round "bass trap" on top is half the circle cut out from the hole. The Fostex F200a driver is my favorite for openness, cleanliness, speed, smoothness, pitch precision, bass punch. But it can be too bright, so I cover them with a grill.

The cabinet at the center is made of .75 inch Russian Baltic birch plywood, glued to .75 inch solid oak, with a eucalytus veneer, and backed with .25 inch cork and .25 inch wool. I've thought to add one wing, but felt the bass did not need it. This cabinet uses the Visaton B200 driver is designed for an open baffle. The sound is harmonically rich and continuous throughout, an easy to listen to and inviting sound. It can sound a bit rough when side by side with a cleaner sounding driver.

The cabinet on right is solid oak. Mounted is the CSS FR125S. In a small room, this driver can sound wonderful. It will not play loud.

This page written October 10, 2006