He sounds like Vernon Dalhart when he sings!
In fact, he was purposely singing in the Vernon Dalhart style.
There were only three people to imitate back in those days:
You can hear Ann Dvorak singing Dalhart's "The Wreck of the old 97" in the 1932 version of "Scarface".
(If you can find some of the earliest recordings of Gene Autry, you'll hear him imitating Jimmy Rogers.)
The earliest song I have in my whole music collection is Vernon Dalhart's 1925 "The Prisoner's So