Time to test a driver almost as old as the DCH. The Goodman Axiette, you can really tell it comes from the 1950s.  Designed by Ted Jordan.

I put a MDF rim around it to get a smoother surface than the OSB. Still the seal is really hard to get as the Axiette is made to be mounted from the rear of the baffle only.

This is the Thile Small parameters of the driver, I have included the curve to show those wiggles in the curve that are intrinsic to the driver. A high Q of 1.0 and a very low moving mass of only 8 grams.

Then the frequency response as measured in nearfield of the cone and at the opening of the pipe.

What I see is a pipe output that peaks well above 50Hz the tuning frequency and an output that is 4 dB below that and sloping around 50 Hz. There is also a hump in driver output at 100 Hz. The 100 Hz hump add some "bassyness" but it lack weight and impact. This is a bad combination.  I am not totaly sure that I got all leaks so some of the flaws might be reduced by having the Axiette properly mounted but I think the high Q will allways lead to a peak around 100 Hz, at least if the DCH is damped close to the original.