Jan 1 2022 is notable as, for the first time, old audio recordings prior to 1923 are included.
Recordings from the dawn of recorded sound were not covered by normal federal copyright protections with expiring terms but were covered by various state laws that gave them perpetual copyright. It was difficult to ever legally clear the permissions to old recordings.
That craziness has finally been swept aside by new legislation that PDs everything prior to 1923 and assigns 100 year expirations to recordings from 1923-1947
Recordings from 1923 become PD in 2024.
https://web.law.duke.edu/cspd/publicdomainday/2022/
On January 1, 2022, copyrighted works from 1926 will enter the US public domain, 1 where they will be free for all to copy, share, and build upon. The line-up this year is stunning. It includes books such as A. A. Milne’s Winnie-the-Pooh, Felix Salten’s Bambi, Ernest Hemingway’s The Sun Also Rises, Langston Hughes’ The Weary Blues, and Dorothy Parker’s Enough Rope. There are scores of silent films—including titles featuring Harold Lloyd, Buster Keaton, and Greta Garbo, famous Broadway songs, and well-known jazz standards. But that’s not all. In 2022 we get a bonus: an estimated 400,000 sound recordings from before 1923 will be entering the public domain too! (Please note that this site is only about US law; the copyright terms in other countries are different.)