I had a similar experience with my Nenuphar Mini’s. Bsically, the first year I owned them it was a love/hate experience. Often, I was enamored with the sound and loved the transparency without harshness. However, as my previous posts mention, I struggled with imaging and often the speakers would "beam" especially with vocals, and/or the soundstage would be tilted to the left side of the listening area, which I attributed to my room. However, I moved houses and have a bigger room and still had the issue.
I upgraded the drivers, tried different components, cables, power conditioners, amps, even Dirac room correction. And I tried positioning speakers all over and adjusted toe in. I even reoriented the entire room which helped but eventually my wife veto’d (to her credit she let me get away with it for a few months). Some changes made improvements but couldn’t quite get it to consistently sound the way I wanted.. One day earlier this year I was getting a little frustrated and went to a local store to demo some Sonus Faber’s which they had hooked up to a Luxman integrated (liked the speakers, but more impressed with the integrated). The imaging was excellent and I noticed the speakers were closer together than I had tried and toe’d in. I had tried putting mine close together but didn’t really try toing in. I went home and started with the speakers really close together (about 5’) and toed in so they "connected" at the MLP. It was an improvement. I started pulling the speakers further apart a few inches at a time and keeping toe in towards the MLP. Eventually I got to the spot they’re at now. I took measurements and made a diagram, just in case they get moved accidentally! Now, I’m getting amazing imaging, detail, depth depth depth (which I think is the hardest attribute to achieve) and tone. Speakers completely disappear. What’s interesting is that I’m pretty sure I’ve had the speakers in about the same spot as I ended up with, but maybe they’re toed in a little more and they’re a couple inches narrower. Just shows a couple inches can make a big difference. I also think it really did take a while for the drivers to break in. If some people say 100 hours, that’s listening for about 2 hours each week. Well, some weeks I don’t listen at all as I travel for work or am too busy. And, when I do listen I would say most of the time is at low volume as I’m working or it’s early in the morning and I don’t want to wake the house. So, it may have just taken a long time to break in the drivers. Either way, I’m loving these speakers at this point. I just acquired a Line Magnetic 845 Premium and I’m blown away by how much better it sounds vs the 518. This is the best sound I’ve ever had and I really don’t think I’m making any changes for awhile. But, I have been following the Sachs 300b thread and might be interested in those down the road potentially, maybe. Once I sell the LM 518 and my Primaluna Evo300 amp (both are excellent but the 845P is in another league) I’ll probably get a solid state amp (thinking Atmasphere GaNFET) to use in the warmer months since the 845P is a heater as well as an amp. But, other than that I am sticking with the Nenuphar Mini’s.