https://www.pbs.org/search/?q=now+hear+this
My List of Best & Most Enjoyable Documentaries (on DVD) about Entire Musical Genre
History of Rock n' Roll, the, (1995) TV series, IMDB 8.2, 10 1hr episodes,
Rock and Roll (1995) TV series, IMDB 8.3
Classic Albums (1997-) TV series IMDB 8.5, 44 episodes
Seven Ages of Rock (2007) IMDB 8.4, BBC Wordwide
VHS Behind the Music (1997-2014) IMDB 7.4
Martin Scorsese presents The Blues - A Musical Journey Blues (2003) IMDB 8.1, PBS
Country Music (2019), IMDB 8.9, PBS Ken Burns, 8 episodes, 16 hours
Jazz - A Film by Ken Burns (2001) IMDB 8.6, 10 episodes
These worthwhile documentaries are mostly about Broadway and the great era of American song writers:
Great American Songbook, the (2003), IMDB 7.6, 175 minutes
Movies of Color - Black Southern Cinema (2002) 55 minutes IMDB NR
Putting It Together (Broadway)
American Cinema - 100 Years of Filmmaking (1995) IMDB 6.3, 544 minutes, a course in Cinema 101, I think it far better than the imdb review. My highly recommended.
Broadway the Golden Age (2004) also titled Broadway: The Golden Age, by the Legends Who Were There , IMDB 8.3
Why no quality documentaries about Gospel or Classical music?