Have only run one audyssey calibration so far, and only taken one set of measurement. The audyssey results were surprisingly good, didn’t have to do any manual adjustment of distances etc to align sub with LCR.
In theory, the SBA/DBA driver placements is supposed to eliminate both the room width and height modes, leaving only the length mode. For SBA, the length mode is managed via thick absorption on the back wall. For DBA, the back wall absorption is done via another array of subs with suitable delay.
The 4 subs on the wall are wired in 2S2P into a 4 ohm load, driven by a single subwoofer amplifier.
i was pleasantly surprised at the almost textbook results, no unpredictable dips in the bass up to 100hz. There are 2 peaks at 20+ and 40+ Hz, those are handily dealt by Audyssey with some EQ.
Sound wise, i guess they sound like what one would expect based on the measurement. Smooth and well behaved, no emphasis on any particular notes. I have since adjusted the room curve to taste using the audyssey app after seeing these measurements.
SBA bass setup is rather obscure, so i wanted to share this in case anyone was wondering about it but too much of a leap of faith to try a build.
Thanks for reading!