Choi Sun Bae (최선배, written 崔善培 in Japan) is a South Korean trumpeter who also plays flugelhorn and cornet and, on a few recordings, harmonica. He belongs to the first generation of Korean jazz musicians and has worked in two worlds that seldom overlap: mainstream jazz and standards in Seoul, and free improvisation, much of it with Japanese and German colleagues. His own releases run from the solo album Freedom (Solo Trumpet Improvisations) in 1999 to the duo Korean Fantasy with the percussionist Kim Dae Hwan in 2023. No source gives his birth date or birthplace. The Hankook Ilbo gave his age as 58 in a profile of December 31, 1999, and a 2020 interview with the saxophonist Sunjae Lee describes him as nearly 80.

A 2025 oral-history paper by Yu Ok-ran in the journal Human and Nature says he first met jazz through AFKN radio in the 1950s, developed his playing in his own way and performed on the American 8th Army stage. The Hankook Ilbo wrote in 1999 that he began playing jazz in 1964 with an 8th Army band and that from 1978 he played at the Korean jazz club Janus, alongside first-generation colleagues such as Kim Dae Hwan and Kang Tae Hwan. His earliest recorded credits are as a trumpeter on pop and film-soundtrack sessions of the 1970s: Lee Jang-hee (이장희)'s 별들의 고향 (Home of the Stars, 1974), and two albums by Jung Sung-jo (정성조) and the Messengers, 어제 내린 비 (1975) and 영자의 全盛時代 (1976).

The turn toward free music came with the Kang Tae Hwan Trio. Korean Wikipedia lists it as the country's first free jazz group, formed in 1978 by the alto saxophonist Kang Tae Hwan, the percussionist Kim Dae Hwan and Choi, and dissolved in 1988. An overseas performance in 1985 with Kim Duk-soo, Kang Tae Hwan and others gave him, by the Hankook Ilbo's account, a real sense of artistic freedom. In 1988 he played the Olympic International Jazz Festival, and the trio, billed as the Seoul Free Music Trio, was recorded in Tokyo at FM Tokyo Hall on June 23 for Kang Tae Hwan's Korean Free Music (Yeh Eum, 1989; reissued in 1998 as Korean Free Jazz). A set from Shinjuku Pit Inn on July 5, 1988, with the same three players, appears on Kim Dae Hwan's Like a Dew Also Like a Thunder (2004).

Japan became his second home base in the 1990s. Takeo Suetomi of Chap Chap Records recorded him at venues in Tokyo and in Hofu, Yamaguchi Prefecture, and those tapes now make up much of his catalogue. A quartet with the tenor saxophonist Junji Hirose, the bassist Motoharu Yoshizawa and Kim Dae Hwan was recorded at the Roppongi club Romanisches Café on June 12, 1995, and the Choi Sun Bae Quartet was recorded at Shinjuku Pit Inn the next day. On August 10, 1995 he played a trio set at Café Amores in Hofu with the tenor saxophonist Mototeru Takagi and Kim Dae Hwan, and on January 2, 1996 a trio set at the same room with the trumpeter Itaru Oki and the bassist Nobuyoshi Ino. On October 27, 1998 Suetomi recorded him alone in Yamaguchi City, and Chap Chap issued the result as Freedom (Solo Trumpet Improvisations). A Hankook Ilbo article headed "The Shock of Korean Free Jazz" introduced the record in Seoul as his first solo album after more than 30 years in jazz and singled out his circular breathing and his multiphonics, notes that sound like two at once. The same piece announced a free-jazz sunrise concert at Seongsan-po on Jeju Island for January 1, 2000, built on "Arirang" and "Our Wish Is Reunification". On November 26, 1999 he recorded a duo concert with Kim Dae Hwan at Aspirante in Hofu, the set NoBusiness Records issued in 2023 as Korean Fantasy.

From 2002 he worked regularly in Seoul with Alfred Harth, the German reed player and multi-instrumentalist who lived in Korea. Harth's Laubhuette Productions, a CD-R label run from his Seoul studio, issued 08 + 15 Celebration (recorded in August 2002), & 5 More With Choi Sun Bae (recorded on December 29, 2002 and January 3, 2003, with the trumpeter Joe Foster) and Choi's own Solo (2007), and Choi appears on Harth's Akupunktur In Gruen, eShip Sum and Ballet Music. He also played in the free-music series held at Bulgasari in Seoul, where the band Ensemble Naeil was recorded on June 15, 2003. In March 2007 he recorded Homura in Seoul with the pianist Yoriyuki Harada and Harth, released by Off Note with a DVD of the sessions. His own web page lists a one-month North American tour in June 2007, a Seoul concert on October 7, 2007 with the bassist Henry Grimes, Harada, Tristan Honsinger, Louis Moholo and Harth, appearances at the Seoul Free Music Festival in 2008 and 2009, and a second American tour in April 2009; those dates come from the page itself.

The documentary Bravo! Jazz Life (dir. Nam Moo-sung, released December 16, 2010), about Korea's first-generation jazz musicians, lists him among its lead cast, and on January 28, 2011 he was one of the veterans who played its soundtrack at the Seoul Arts Center. He was also the trumpeter in the pianist Shin Kwan-woong's first-generation band, which held a regular Thursday night at the Hongdae club Moon Glow from 2003 and played what the Sports Hankook called its last night there on December 30, 2010. In May 2011 FarGo Music released A Trumpet in the Night Sky, standards for flugelhorn and trumpet with a string ensemble, arranged and conducted by the pianist Cho Yoon-seung (조윤성), who produced the record with Choi. The two appeared together that year at the Jarasum International Jazz Festival, and on February 29, 2012 Choi was one of six nominees in the Best Jazz & Crossover Jazz Album category of the Korean Music Awards, which BG Salon won.

NoBusiness Records of Lithuania then issued a series of the Chap Chap concert tapes: Kami Fusen (2017), Arirang Fantasy (2018), Seishin-Seido (2022) and Korean Fantasy (2023). Chap Chap itself put out The Sound of Nature Live At Shinjuku Pit Inn on LP in 2015. In Seoul he recorded Palindrome in 2020 with the saxophonist Sunjae Lee and the drummer Junyoung Song for Lee's new label Mung Music. Lee said that after a 90-minute solo set at the Ghetto Alive club he began playing with Choi, whom he called the first true elder of the scene willing and able to back young Korean improvisers.

Jazz Tokyo's report on the Kim Dae Hwan memorial concert at Gallery MAI in Hofu on May 25, 2024, held 20 years after the percussionist's death, says Choi had been out of active performance since March 2023 but agreed to cross over from Korea for the day; his solo "Mona Lisa" ran through the ensemble. Chap Chap issued a Kim Dae Hwan live set from 1994 with Choi, Hirose and the drum master Shonosuke Okura in 2024, and Okura's tribute record Iyasaka, with Choi on two tracks from that memorial, in May 2026. In October 2025 Yonhap announced him as a first-generation master of free jazz in the Mapo Culture Foundation's 2025 Jazz All-Stars concert at Art Hall Mac in Seoul on November 21, 2025.

His own biography, repeated in NoBusiness's release notes, describes a clear, lyrical sound on trumpet, cornet and flugelhorn, an ear for the beauty of the whole ensemble rather than solo display, and a preference for tone over phrasing. It also presents him as both an accomplished mainstream player and a free improviser, which the discography bears out: the string-backed standards of A Trumpet in the Night Sky (2011) sit beside the free duo of Korean Fantasy (2023). The Hankook Ilbo described a soft, flugelhorn-like tone that follows sharp high notes.

Tributes recur. Arirang Fantasy includes "Remember Bird", an homage to Charlie Parker, and he plays "I Remember Clifford" on both Kami Fusen and A Trumpet in the Night Sky. The 2025 oral-history paper sums up his outlook in three values: challenge, freedom and humility.

His partnerships shape the sound. Jazz Tokyo's Kimio Oikawa heard the trumpet and Hirose's saxophones merge into one sound image on Arirang Fantasy, with a duet for the two of them on the second track. On Korean Fantasy he plays electric as well as acoustic trumpet and harmonica against Kim Dae Hwan's Korean drums, struck in a one-beat style, in three long dialogues of 33, 13 and 8 minutes. Korean song runs through the titles: "Arirang" opens Freedom and gives Arirang Fantasy its name, and "Korea Fantasy" is its fourth track.