Unfortunately, Dhaan above is correct about the WP and the hot Focal tweeter -- the breakup resonance indeed causes distortion throughout the presence region, and this is plainly audible in the original Focal (JM Labs) Utopias and the Wilsons.
I don't agree if you are referring to the W/P8 tweeter. I even ran some tests and eliminated it as the cause of issues Dhaan said he had heard with soprano and violin (he said any soprano and violin material would reveal it). He won't give me any specific recordings to test, so I can't figure out specifically what was causing the issues he was hearing. The break up mode should be below adult hearing threshold unless you are a pre-pre-teen.
If you want to give me some music you heard the problem on, as well as specific times and locations on the albums, I'll be glad to figure out what you were hearing. If it was tweeter break-up, which I doubt because of the high frequency location of the break-up mode, I'll be glad to confirm it or figure out what it is. I also have the ability to test it on three decent speakers (as I did previously with only two speakers).
I'm not sure about the W/P7 if that is what you are referring to... The W/P7 and W/P8 use different tweeters...