Chu auditioned at SM in 2001 and received a standing ovation by Lee Soo Man.

On the radio show Ahn SeonYoung's Radio Is Good on May 19, Chu Ga Yeol said "Among the hoobaes of Super Junior that I taught how to play the guitar, Sungmin is the one who learnt to play well right away.

To see a hoobae like Sungmin’s improvement in guitar skill, I feel so proud and it's very rewarding."

Sungmin had previously said to Chu "If there are chances, I want to play the guitar on stage with you."

The two would later perform a cover of "Just The Two Of Us" at SMTown Live '08 and Chu Ga Yeol's X-Mas Concert.