Updated to show finished design and details: This design uses the Celestion TF0818 and the DNA-150/DW-774s, goal was to have a compact bookshelf that had high efficiency, good dynamics, decent extension, smooth articulate sound and do so with a budget of around $100 for drivers and crossover parts per speaker. Finished enclsoures: On axis FR: 0-50 degrees horizontal off axis response: 0-20 degrees below axis: 0-30 degrees above: Finished Crossover, input is on left, woofer out top left, tweeter out top right: Schematic: Original build start point: Finally started this build yesterday. Using the DNA-150 CD in the DW-774S waveguide, with a Celestion TF0818 for the low end. Enclosure is approximately 0.6 cu ft internal tuned to 70hz, F3 sould be right about 80hz. Dimensions: External 19"h x 9"w x 10.25"d, Internal 18" x 8" x 9", Slot port 1.5"h x 7.5"w x 7.5"L, Drivers flush mounted, the DW-774S was a pain in the @$$ to flush mount, I had to do it all with the router by hand. Mostly finished with enclosure construction but needs a few more things done before I throw in the drivers and start measuring. Just building the one and going to leave it unfinished until I decide if I want to build another mdf box and paint them black or make nicer enclosures for the pair.