It's not speaker burn in, it's your reference sound burned in your brain that sets the bar for what you think/know as good sound. ...
The first time anyone gets a new speaker you have a bias even though you may consciously know about it, but ultimately your reference sound starts with what you have known for a long time, the M80 sound. ...
This kind of "reference burn-in" makes perfect sense, and in fact it occurred to me when I was listening. Worse for a comparison, it's a significant improvement on the kind of response I've been listening to for 50 years so really want that improvement.
I observed the same thing you mentioned re: the soundstage. With the LFR i noticed that the sound was more dispersed and less directional or at least less noticeably directional. ... (my listening experience happened at the Axiom factory so over a very short period of less than 1 hour).
This also makes a lot of sense. Truth is, when I started less than 40% of the samples sounded better on the LFRs. So over the roughly 12 hours time the LDRs gained ground. But, it's the "smile score" that will probably keep me from continuing the comparison for very much longer. That and the fact that because I know I'm returning one set I've been treating them with kid gloves and I'd like to stop doing that and set them up permanently.
... Assuming the algorithm for deriving the listening window and sound power is the same for 80 and 660, I can't see how the 80 can sound better given the more linear behavior of the 660. I will say that positioning matters a lot. Maybe the algo is not the same and that means we can't directly compare the curves of the two.
My active LFRs blow the M100v4 away in absolutely every category. But I had to fiddle with positioning for months to achieve Nirvana. ...
Looking at he published curves, I wouldn't say that the LFRs are more linear (by the usual audio use of the word, and in the listening window), I'd say they have better room resonance response.
I didn't play with positioning much, and I feel bad about that, but like I said above, after all this time I'd really like to move into the enjoying phase! (Also, I used up the 30 days review time on the M80 already because I asked for them to be shipped early when there was a chip delay. I suppose I could ask Axiom for more time; but again, I'm getting impatient.)
As far as the single positioning though, the LFRs had the primo spot being positioned precisely 12 inches from the back wall and away from the side wall. The M80s were then placed next to the the LFRs; one M80 had no rear wall; or rather, it had an additional 6 feet, into the hallway.
I'm definitely not pretending I'm making an audiophile choice; this is pure and simply which one I like more.
