Hi Bill, I am new to SEOS, but I have built and owned Tom Danley's Unity Horns from about 10 years ago. I am not a designer...just a builder, and I noticed this thread because I have a pair of Lambda TD15M's hanging around that I would like to build into an MTM center speaker, just to compare to the Unity Horns. Do you have an MTM version of this design? Specifically, I would need to know how to modify your crossover to accomodate the extra 15" driver in an MTM configuration, as I have no knowledge of crossover design. Thanks!