In that room we have 3 different bass solutons working toghether,  2 ten inch pro woofers per side from 140 hz down to fs cutoff (around 45 hz) sealed enclosures, and a pair of 15" servo controlled subwoofers one per side  taking it from 50 hz.  And well the tapped horns, that add a nice punch to it all.
  The big problem with this setup is time aligning everything, or finding the correct phase for all the bass drivers: If something is not perfectly in sync,  the woofers start fighting each other and you get a real mess!  We found out once that by lowering the volume of one channel we got more bass output!!!  Something was clearly wrong!
 
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