The MicroWrecker?
The littler brother of the LilWrecker. Guess I can let that kitteh out of the bag too...
It is a 20 cubic foot tapped horn that is tuned a little higher and gets a little louder.
Cabinet is approximately 4' by 2' by 2.5', I loaded mine with a CVX-15, cause that's what I have.
It's real, I've built the proof of concept/test mule, and am currently listening to it.

No accurate measurements that I 100% trust yet, but my preliminary ones suggest that the response is very similar to Ricci's Gjallerhorn,
though I'm leaving the top 6 dBs on the table cause the CVX-15 is a pea-shooter when compared to the LMS-Ultra...

Based on the issues I encountered with my first build, I have changed the design a bit.
I have wood ready to cut for the second, which is the build I'll document.