The One (더 원), real name Jung Sun Won, is solo artist under F&F Entertainment and is Taeyeon’s vocal instructor. Having debuted in 2002, The One has lent his vocal talent to many popular K-drama sound tracks such as “Goong,” “My Man’s Woman,” and “Rosy Life.”
Taeyeon has also worked with The One in his track “You Bring Me Joy (Part 2)” in 2004 when she was only fifteen years old.
If you are interested in The One’s music, visit his Daum cafe here. It will also help to search his Hangul name (더 원) to Youtube to find better results.