I have never heard them, but if you look at the FR measurement, you will find that these particular headphones are simply trash.
https://headphones.com/blogs/reviews/austrian-audio-hi-x55-the-comeback-kid-and-the-closed-back-curse

Much better than all monitoring headphones and even audiophile ones in my opinion.. Get them if you want to hear the true sound of the recording, the source (to which they are connected) without any coloration in the bass and highs, with deep soundstage and VERY DETAILED! For me, the best headphones by far!