[4] Son is the younger of two children and was born in the United States to Korean parents who are naturalized American citizens.

[6] Son was elementary and middle schoolmates with Kang Sung-hoon and Ko Ji-yong, both of whom went on to form Sechs Kies.

[19][20] Ahn was recruited by his cousin Park Joon-hyung to join his project group under EBM and persuaded Son to audition.

[21] With Park Jin-young as their producer and primary songwriter, the group eventually became a five-man boy band g.o.d, short for "Groove Over Dose", and made their debut in January 1999.

Son and Park signed individual contracts with JYP Entertainment while Yoon and Ahn remained with SidusHQ.

In 2007, Son released a single album entitled Sweet Love; the lead song is "My Heart in Heaven" (Korean: 하늘에 내 마음이; RR: Haneure nae ma-eumi).

The promoted single "Pretty But Hateful" (Korean: 예쁘고 미웠다; RR: Yeppeugo miwotda) featured rapper Bizzy, best known as a member of pioneer hip hop group Drunken Tiger, and peaked at #72 in the Gaon Digital Chart.

[31][32] From November 25, 2011, to January 29, 2012, Son starred in the musical Fame along with Eunhyuk of Super Junior, Tiffany of Girls' Generation, Go Eun Seong, Kim Chan Ho, Shin Ui Jeong, Lina of The Grace, Choi Ju Ri, KoN and Kim Jung-mo of TRAX.

[33][34] In 2013, Son participated and won in MasterChef Korea Celebrity alongside other Korean celebrities, Seo Hye-jeong, Lee Kye-in, Shin Eun-jung, Kim Sung-soo, Tony An, Shin Bong-sun, Hwayobi, Fei (Miss A), Henry (Super Junior-M) and Jiyul (Dal Shabet).

[37] They largely concentrate on releasing new material and holding live concerts rather than promoting on music programs to allow individual members to concurrently maintain their solo careers.

Son recorded the ballad "One Day" (Korean: 하루만; RR: Haruman), one of the soundtracks for the tvN drama series Marriage, Not Dating.

[38] It was first played during the closing credits at the end of episode 8, which aired on July 26, and the accompanying music video uploaded later that week by CJ E&M.

[42] He was a guest judge on No.Mercy, a survival program launched by Mnet and Starship Entertainment in 2015; the seven of the remaining contestants would debut as Monsta X.

[45][46] The music video for the title track "My Weak Point" (Korean: 나의 약점; RR: Na-ui yakjeom) was uploaded on CJ E&M's YouTube channel.

[49][50] The repackaged album, which included an additional new single "None Like You" (Korean: 너 같은 사람 없어; RR: Na gateun saram eopseo), was released in October.

[55] He was one of eight guest artistes featured in his bandmate Kim Tae-woo's sixth solo album T-WITH, which was released in June 2017.

[60][61] Son put his solo activities on hold for the latter half of 2018 due to g.o.d preparing for a series of projects celebrating the 20th anniversary of their debut.

[63] As HoooW, they have appeared on Immortal Songs: Singing the Legend and You Hee-yeol's Sketchbook and performed as guests at Psy's summer concerts.

On August 16, they released the digital single "Game Over" (Korean: 친구는 이제 끝내기로 해; RR: Chinguneun ije kkeutnaegiro hae).

[68] Son was cast in the musical Chunhyang is Alive (춘향은 살아있다), a modern interpretation of the pansori Chunhyangga.

[74][75] It was reported in March 2006, after g.o.d discontinued group activities, that Son had undergone surgery on his right knee as it had never fully recovered since the accident and that he had been performing throughout the God is Back National Tour while on painkillers and delayed treatment.