Aha, I think we may be getting closer to the issue you are experiencing.
If you would advise me of a pieces of music that you experience this, specific Artists and Tracks and I will have a listen, don't tell me what or where it is you hear any issues, it would be best if it is on CD or digital and then I can source it, but you never know I may have a copy on LP anyway. I will listen very carefully on my system and try and be as analytical and critical as possible, and see if I find any issues, I know it is a bit subjective but at least you would have a view, if I hear distortion or harshness of any sorts I will honestly report it to you. My Wilson Benesch speaker are very revealing of dodgy recordings or mixes, I have a few that I find annoying.
Just for info I looked up the frequency ranges of wind instruments:- see
https://onlinelibrary.wiley.com/doi/...119164746.app2
The AN J's employ a 8" driver that does the mid-range and bass, I believe it is generally considered quite a hard ask for such a driver to cope with both low-mid and upper mid at the same time. I believe the tweeters will be dealing with much higher frequencies. Most reviews actually say that the mid-range from AN J's is pretty good, so it would be interesting to know exactly what and when you experience the harshness you describe. Certain instruments are notoriously difficult to reproduce accurately so maybe that has something to do with it.
Thinking about it, it could be that you could have golden ears, in other words you detect pitch and its accuracy very naturally so anything reproduced slightly off becomes annoying or dissonant to you, it is not unknown. Some people and musicians have what is called natural pitch perception, that is they instinctively know when something is in tune or slightly out of tune, others have to develop this ability with time singing, playing instruments and listening to others.
Cheers
Adrian]