Is that a brand or are they actually putting beryllium oxide in headphones these days?
[0] https://www.bang-olufsen.com/en/headphones/filter/over-ear
[1] https://blog.masterdynamic.com/article/know-your-sound-tool-...
[0] https://www.bang-olufsen.com/en/headphones/filter/over-ear
[1] https://blog.masterdynamic.com/article/know-your-sound-tool-...