secretguy
I guess HDCD failed in the marketplace.
I don’t think it’s dead, as I believe Reference Recordings ( Keith O. Johnson) still use it, with 16bit and 24bit recordings.
https://referencerecordings.com/
https://referencerecordings.com/?s=HDCD
As do some hiend Japanese studios.
I think it sound magnificent, especially if you have a cd player or dac that had the last hdcd chip, the PMD200, the 100 was very good still but the 200 is something else.
If your interested in getting one used, type in PMD100 or PMD200 in the search bar of this vast data base of players and dacs that used them. http://vasiltech.narod.ru/CD-Player-DAC-Transport.htm
Cheers George