The correct spelling of the phrase "letted be known" is actually "let it be known." This phrase means "to make something publicly known or communicated." The word "letted" is an archaic form of the verb "let," which means allow or permit. The correct conjugation in modern English would be "let." The pronunciation of "let" is /lɛt/, which rhymes with "pet" and "met." Additionally, "it" is pronounced /ɪt/ as in "sit" and "kit."