As regards plopping, based on the DBA concept one merely needs good asymmetrical positioning around the room. Of course more adjusting could be done, ad infinitum I suspect. Sometimes you do your best and call it a day. I’m already happier without going wild on positioning, yet…
And my ears did not adjust the bass levels. I wanted the flattest, lowest bass possible with no humps or exaggerations so I ran lots of frequency sweeps down to 20Hz in 1/3 octaves and dialed it all in without my ear. That gave me a pretty flat bass down past 31Hz.
The true ‘proof is in the pudding’ moment was when I played the first track (Signe) off of Eric Clapton’s “Unplugged” album with the three sub-woofers dialed in. For the first time I noticed the air pumping or chuffing coming from something on-stage just past the two minute mark. I was amazed as it was so soft and so low in tone I barely picked it up. Now I know it is there. An ‘ah hah’ moment.