In 2001, before his debut, Kim Hyuk Gun (김혁건) won the Grand Prize in the Rock Solo category at the Mnet Music Festival. Two years later he debuted as the vocalist of the rock band THE CROSS (더크로스), and "Don't Cry," from the band's first album "Melody Quus," was a song whose top note went above the third octave.
This article is for readers asking what kind of vocalist Kim Hyuk Gun is. It follows his range and technique, what others have said about his voice, and the rock roots traced by the songs he chooses to cover.
01.A Grand Prize Before the Debut, and a Name That Came With It
Kim Hyuk Gun's name first appeared on a rock competition stage. At the 2001 Mnet Music Festival he won the Grand Prize in the Rock Solo category, and that award opened his way into a singing career. In 2007 the Korean outlet Mydaily introduced him as a singer who debuted on the strength of that prize.
When he debuted with member Lee Si-ha (이시하) as THE CROSS in 2003, the band soon gained a nickname. In a 2014 article, Etoday wrote that THE CROSS earned the title "supreme vocalist" (보컬의 지존) with its debut.
The verdict of someone who heard that voice up close is on record as well. Kim Tae-won of Boohwal (부활), who produced THE CROSS's first album, said on JTBC's "Re:Alive" in 2023: "Kim Hyuk Gun's high notes were elegant." It is a remark about the quality of the high notes before their size.
02."Don't Cry," a Song Above the Third Octave
"Don't Cry" reaches a top note above the third octave, and around his debut Kim Hyuk Gun made his name with three-octave shouting high notes. Why the song has so many high notes comes from the singer himself. In a 2020 YTN radio interview, he said "Don't Cry" was made with many high notes "to show my high notes as much as possible."
The direction of the song was also a choice made by the people behind the debut album. Kim Nam-hyung (김남형), the head of the company that produced the album, said that at the time there were no songs in Korea in the style of X-JAPAN, so he expected "Don't Cry" to stand out. Melon's artist profile describes it as the song that became a men's karaoke favorite for its high notes — and the people who tried to climb its chorus in karaoke rooms back then have now lived through more than twenty years.
The 2003 broadcast stages and the 2023 20th anniversary version are covered in Don't Cry: The 2003 Original and the 2023 Anniversary Recording.
03.Head-Voice Scratch Over a Natural Clear Tone
How are those high notes produced? In a 2019 music column for Maeil Business Newspaper (매일경제), reporter Hong Jang-won (홍장원) described Kim Hyuk Gun's technique as building on a natural clear tone (미성) and reinforcing its power with a distinctive head-voice scratch. The same column wrote that even when he sang extreme high notes above the third octave, nothing sounded forced, and it placed the top note of his 2007 solo song "Warrior" (나만의 그대) at A in the third octave.
There is also a record that traces his technique to classical singing. In 2007 Mydaily introduced Kim Hyuk Gun of Rockband Cross (락밴드 크로스) as a vocalist using a head-voice technique grounded in classical vocal training, and articles that year described Rockband Cross's music as ranging from plaintive ballads to high notes over a hard rock sound.
A natural clear tone, a head voice drawn from classical singing, and a scratch laid over it — two records twelve years apart point to the same place.
04.From Black Sabbath to Blackhole
Where Kim Hyuk Gun's voice comes from is told by the songs he chooses. THE CROSS's first album was a straight rock record produced with senior members of Boohwal, and in 2024 Kim Hyuk Gun said, "We, THE CROSS, are a band that was really influenced by him (Kim Tae-won)." In 2014 Etoday wrote, "Kim Hyuk Gun was always thirsty for rock music." As of October 2026, Melon lists his genres as rock/metal, indie and ballad.
That thirst shows plainly in the cover list on the official YouTube channel, THE CROSS OFFICIAL.
| Song | Original artist | Style | Official video released |
|---|---|---|---|
| Heaven and Hell | Black Sabbath | Heavy metal | 2026.09.23 |
| Burn | Deep Purple | Hard rock | 2026.02.08 |
| Mr. Crowley | Ozzy Osbourne | Heavy metal | 2025.10.06 |
| Stand In Line | Impellitteri | Heavy metal | 2025.08.13 |
| Rising Force | Yngwie Malmsteen | Neoclassical metal | 2025.01.07 |
| ENDLESS RAIN | X-JAPAN | Rock | 2025.02.11 |
| Farewell To Love | Sinawe (시나위) | Korean metal | 2024.07.11 |
| 내 곁에 네 아픔이 (Your Pain Beside Me, unofficial translation) | Blackhole (블랙홀) | Korean heavy metal | 2026.07.01 |
The hard rock and heavy metal classics of Black Sabbath, Deep Purple and Ozzy Osbourne; the metal of Impellitteri and Yngwie Malmsteen; X-JAPAN, linked to "Don't Cry"; and the Korean metal of Sinawe and Blackhole — one list becomes one vocalist's lineage.
The story of each original and the musicians who played on these covers continues in THE CROSS Band's Rock Covers.
05.The Singer Who Studied the Voice
Kim Hyuk Gun is also a singer who has put his own voice into writing. He published the vocal method book "Cross Kim Hyuk Gun Vocal Lessons" (크로스 김혁건 보컬강좌) in 2014, and in 2019 he received a Ph.D. from the Department of Applied Arts (Practical Music major) at the Graduate School of Kyung Hee University. His dissertation, 「횡격막 마비군과 비마비군을 통한 복식호흡과 발성법 연구」 ("A Study of Abdominal Breathing and Vocal Technique in Groups With and Without Diaphragmatic Paralysis," unofficial translation), tested through experiments that abdominal breathing is a key factor in widening vocal range and in crossing the passaggio, the zone where the voice turns toward its high register. The dissertation concludes that a balance of force between the diaphragm and the vocal folds makes it possible to carry high notes and resonance through the passaggio, and his own "Cross Kim Hyuk Gun Vocal Lessons" is listed among its references. Kim Hyuk Gun's singing is grounded in this research.
The dissertation can be read in a 24-part series, starting with Part 1 · Study Overview.
06.Where to Listen
"Don't Cry" and the cover videos are on the official YouTube channel THE CROSS OFFICIAL and on the website's Music page. Who Kim Hyuk Gun is can be found in Kim Hyuk Gun: Official Profile and Name Guide, and the band he plays with today is on the THE CROSS BAND page.
From a rock competition in 2001 to a Black Sabbath cover in 2026, the songs this voice has chosen have pointed in the same direction from the start.