You can do much better for way less. My last DIY speaker used the same mid and high drivers PS Audio uses....but I used them on an open baffle with much better parts and no padding.....way, way better. However, those particular B&G drivers are not available to the public anymore.
BUT......you can do even better. Make your own open baffled 2 way biamped speaker that will blow your mind. You use the Minidsp Flex for the preamp/crossover/room correction/volume control.........its $500 but will sound better with dedicated serious power supply. The speaker would be an open baffle speaker 16 inches wide at the bottom and you would mount 2 ($160 each) Beyma 12 inch BR70 speakers (pretty sure these are the same woofers used by Spatial Audio in their $9800 open baffle speaker, however they pad the woofers with distortion producing coils and only get 88db sensitivity). Run without passive crossover and In parallel they would be around 93db sensitive.....above it on the same baffle you can use one of the $60 planars from Parts Express......or 4 of them in series parallel.....or you can use one of the 10 inch planars from Radian ($350 each). You use your current amp on the over 90 db planar/s and get a cheap amp to drive the woofs. Total price for the xover, better power supply, 4 woofs, 2-8 planars, wood, wire would be $2K or a little higher..... and then just add a bass amp of your choice.....heck even the $80 Fosi amp would drive the woofs to over 100db. This fully open baffle speaker when equalized and time aligned would have flat bass to 30hz and be a gazillion times more transparent than the PS Audio. We are talking no Chinese xover parts.....we are talking the wires from the amps are soldered to the drivers.....all open baffle...time aligned.....everything easy to drive (above 90db). You could make a test baffle and start listening in one afternoon.....even a 10 year old can do it. If someone wants to try this and wants help.....give me a call....I will help you for free (pretty darn simple really).