Why do actors in old American (40s or earlier) television sound so different? Has the “American accent” changed?

by govzzz

My dad guesses they sounded so different because many actors were originally stage trained, meaning they spoke and projected differently. I thought it was due to changes in recording equipment or evolution of the way the American accent sounds. Does anyone know? Are either of us correct?

Gankom

While more can always be said, you might enjoy this older answer on a similar topic.

Why do actors talk so oddly in American 1950s sitcoms? from /u/Dont_Do_Drama.

[deleted]

These older posts might also be useful.

Are accents, slang and postures in old movies accurate? Or are they a bi-product of actors coming from theatre to the new medium of film?

Watching American black-and-white movies, there is a certain somewhat unexplainable "way" people talk and act, and people's personalities are different than today, but seem a little weird to be every day life. Did people really talk and act like that outside of movies?

Have American accents changed over the past 60 years? Watching old movies and the people talk very differently.