Twain's voice was recorded many times, but there is no confirmation of a
single survival.

He filled about 100 wax cylinders dictating AMERICAN CLAIMANT (1892), he
walked in on a recording session of opera diva Nellie Melba and made some
remarks when he realized he was being recorded, his 1905 birthday speech was
recorded but does not survive in the personal or corporate archives where it
might have been expected to survive, he dictated letters on wax cylinders to
his stenographer, and Edison recorded Twain's voice when he visited
Stormfield and filmed him, but that recording was lost in a 1913 fire at
Edison, and does not show up in any commercial listings by Edison (Edison
did sell cylinders of others imitating Twain and telling his stories --I
have one such example). During World War II an unidentified recording (one
of the above?) of Twain's voice was lost in France. Perhaps it survives, or
was copied. There are probably others I've not remembered. C'est la vie.

The jumping frog recording by William Gilette was made ca. 1922 for a
Harvard group, and WG was still doing it in the 1930s for other groups. On
some versions of that recording he can be heard introducing himself. That
commonly played recording is often mistaken for Twain. Hal Holbrook used it
as a model, and his imitation was later pronounced perfect by Clara Clemens,
although her endorsement of anything at that point in her life could be
questioned. But Gilette grew up in Nook Farm, heard Twain's voice in person,
and was a talented mimic, so his recording can certainly be accepted as
reliable, and therefore, HH's as well.

A note about the Gilette impersonation: the text recited by Gilette varies
from the printed text, and the nature of the textual difference is similar
to the kinds of differences that exist between Twain's other written and
oral texts (his oral texts are reflected by markings he made in his reading
copies of his texts, of which I have two heavily marked volumes in my
personal collection). This could indicate that Gilette was aware of Twain's
oral text from some source --perhaps a recording of the same story by Twain?

One oddball footnote. I have an advertising packet from a company that sold
"wire" recording equipment during Twain's lifetime that recorded both on a
strand of wire and on a disk much like a modern CD. They used Twain's name
in their advertising, but stopped short of implying that he actually used
their product or anyone else's.

Kevin Mac Donnell
Austin TX