Difficult to say. There was no way of recording voices back then! Also grammar, spelling and pronunciation changed. Have a look at this article in Wikipedia.
As to a good guess as to the actual sounds, have a look at the suggestion by in #41 by Hermione Golightly.The Great Vowel Shift
The Great Vowel Shift was a series of changes in the pronunciation of the English language that took place primarily between 1350 and the 1600s and 1700s, beginning in southern England and today having influenced effectively all dialects of English. Through this vowel shift, all Middle English long vowels changed their pronunciation.
Great Vowel Shift - Wikipedia