The group consisted of five members: Jungkyun, Seunghyun, Soul J, Yujin and Sangwoo.
[1][2][3] Prior to debut, N-Train trained with their agency for three years.
[4] In hopes to break the idol group image of recording dance-type music, MediaLine Entertainment directed their attention in recording R&B and soul-oriented music instead.
[5] N-Train debuted with a mid-tempo ballad song, "울면서 울어 (One Last Cry)", on May 27, 2011.
[6] In one of their music reviews, a staff writer from Allkpop complimented their debut single, noting that "N-Train will find most of their appeal is surprisingly through their singing, because boy is it good."