There is an interesting phenomenon I've read about where distant colonies, kept isolated from where their language originated, end up sounding more archaic than their home territory. The act of crossing an ocean can serve as a linguistic time capsule and changes made in the homeland don't always propagate.
I've heard this claimed about a few languages:
* Quebec French vs. France. (true to the form of TFA I do not speak French, so I cannot assess this claim.)
* Judaeo-Spanish spoken by expelled Jewish communities vs. Spain. (from what I recall of recordings of the former it did seem like it lacks some phonetic changes that Spain had around the 15th-16th centuries, like [ʒ] and [ʃ] moving to [x], loss of initial /f/ in words like hijo, hablar ... and consequently generally has this almost Portuguese-sounding feel to it. Interestingly these same phonetic changes made it across to Latin American colonies but not to expelled Spanish Jews in Europe)
* American English vs. England. (I've heard this claimed variously, as if to say that Shakespeare spoke with one of today's American accents, and frankly that sounds kind of dubious. But there may be bits and pieces of American English that sound old fashioned across the pond.)