There are those headphones, X5h from MAS, I made a video about
Also I wrote a review about the only headphone in the world at this moment which is supposed to have a Tube inside
https://www.audiophile-heaven.com/2019/07/sweet-and-juicy-ovc-vacuum-tube-headphones.html
The OVC tube headphones are a killer idea. Do you know when they are going to release these?