I realize that in-room response is highly room dependent and hence I use MSO. However, rightly or wrongly I also had the distinct impression that the PV1d itself was sounding cleaner. The measurements posted here by Nuyes do show quite distinct differences other than CEA, so I am wondering if those differences are indeed audible.
I tend to like the sound of one very clean sub when in mono, or two subs with stereo, .... always collocated with the main speakers. I like this better than MSO.
But they have to be "very clean". What does that mean? Hell if I really know....
I've built a number of DIY subs and measured then extensively, trying to correlate measurements with hearing perception.
About the only think I'm confident of....because I can't really tell which......THD, IMD, CEA-2010 or yadaD measurement......correlates with my hearing perception of "cleanliness."
The only thing i feel confident about, is the higher the SPL the sub can continue to measure relatively low THD, IMD, CEA-2010......the better is seems to sound at normal SPL.
Maybe that's pure confirmation bias...I dunno.
All that said, I believe in speakers that are totally loafing at normal SPL....with vanishing low measureable distortions.
Totally loafing is my goal with DIY...
Here's a sub example...a dual 18"
CEA taken out in the yard with REW
Distortion taken on the driveway. 125dB @1m
So I figure a box with that kinda output stays clean,....uncompressed, unclipped, and undistorted at high normal SPLs, including full room for transient peaks.
My solution of ........"I can't make sense of separating what distortion really matters, so just overbuild to cover them all"