SIYUN
AMPERS&ONE · Main Vocalist
Profile
SIYUN (Yoon Si-yun) is a main vocalist of AMPERS&ONE. He brings melodic range and expressiveness to the group’s songs, especially the more emotional entries in its discography.
Before debut, he participated in the competitive YG Treasure Box programme. That early exposure and continued vocal development led to his selection for the FNC team in 2023.
On DEFINITION, SIYUN identified Tears in your smile as a particularly personal vocal showcase, citing its emotional delivery. His repertoire spans energetic hip-hop-inflected singles and reflective pop album tracks.
SIYUN continued the band’s overseas tour programme in 2026, including European dates under the Born To Define banner.
Career Milestones & Individual Activities
Born To Define · European stages
Took part in AMPERS&ONE’s concert activities across six European cities.
K World Dream Awards
Received the group-level Global Next Leader recognition with fellow members; this is not an individual trophy.
DEFINITION and GOD
SIYUN contributed to the fourth mini album and performed its title song. The release broadened the group’s sound and staging.
Tears in your smile · vocal performance
Named the emotional album track as closely aligned with his vocal character.
LOUD & PROUD
Participated in the EP and its title-track promotions for That’s That.
AMPERS&ONE debut
Debuted as a vocalist and recorded On And On.
Pre-debut competition
Appeared on the YG survival programme before further training.
Member News & Further Reading
Agency notice lists six European stops and dates.
August 27, 2026 · FNC Official2026 K World Dream Awards group honour ↗Agency page lists the seven-member team’s Global Next Leader award.
June 18, 2026 · Korea JoongAng DailyAMPERS&ONE’s first European tour ↗Independent reporting on the September six-city concert programme.
April 28, 2026 · DAVIDE K-POPSIYUN · Singing with sincerity on Tears in your smile ↗A personal quote in an interview about DEFINITION and the group’s development.
April 14, 2026 · EARMILKSIYUN in a DEFINITION group conversation ↗International member interview on composition, recording and ambition.
April 8, 2026 · Korea JoongAng DailyIndividual images from the Seoul showcase ↗Photographs and reporting on members during the DEFINITION press stage.
April 8, 2026 · Unclear MagazineSIYUN’s answers on new music ↗Member interview covering identity, tracks and the group’s international fans.
2026 · FNC EntertainmentOfficial member profile, awards and albums ↗Primary label source for official group membership and dated releases.