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K-Pop duet collaborations are always a wonderful experience, especially when these involve members of different groups coming together. To see fandoms come together to support their favourite artists, and to hear the unique blend of their vocals is always a delight.
Today brings with it another fresh collaboration with two groups that both entered the scene around the same time. OMEGA X’s (and sub-unit OX:N)’s maknae Yechan collaborated with CLASS:y’s Hyungseo for a fresh new single , titled ‘들었다놨다 (Up and Down)’.
As is always the case in K-Pop, the process of song creation is a highly collaborative process that often reaches far beyond the performers. With this particular project, production/songwriting team ‘CIELOGROOVE‘ took the reins. This team are well versed in the industry, having previously worked with artists including Kim Jaejoong, WEi, and BAE173. They have also worked on survival programs like JTBC’s ‘Peak Time’ and SBS M/SBS FiL’s ‘SCOOL’.
Speaking on the project, OMEGA X member Yechan had the following to say:
“It feels quite nervous to release my first duet track with a female artist! For this project, I tried my best to highlight a softer voice than the energetic one which I’m more used to, and I’m glad to hear that my voice carried the emotions of the song well.”
“들었다놨다(Up and Down)” is a refreshing song, centring acoustic guitar rhythms and smooth melodies to capture the back-and-forth dynamics involved in the early stages of a romance. In this way, the excitement of falling in love and playing hard to get are expressed through the vibes of the track. The track is also accompanied by a studio music video featuring both Yechan and Hyunseo‘s expressive vocal deliveries.
This project is actually the second duet project produced by CIELOGROOVE in 2025. Their previous duet project was the song ‘좋아한다 말할래 (I wanna say I love you)’ which featured GK and Song Sun of girl group TRI.BE, released in April of 2025.
Furthermore, it has been a very busy year for Yechan. Yechan previously debuted as a member of OX:N (OMEGA X’s first sub-unit), on June 20th, 2025. Fans can look forward to fun activities from the unit in September, as they host their first fan meeting ‘INTO:N‘ in Tokyo on September 10th and 11th, alongside further promotions in Korea, Shanghai, and Macao.
ABOUT OMEGA X:
OMEGA X is an 11-member K-pop boy group under IPQ. The members include Jaehan, Hwichan, Sebin, Hangyeom, Taedong, Xen, Jehyun, Kevin, Junghoon, Hyuk and Yechan.
Their name also holds a special significance. Taken separately, it has a dual symbolism. The Greek letter Omega (Ω) is the last letter of their alphabet and signifies an ‘ending’, meanwhile ‘X’ is universally recognised as a mathematical symbol of the unknown or of infinite possibilities. Combined, OMEGA X is a powerful name, showcasing the group’s determination to become the last boss of K-pop, symbolizing constant change and growth.
This is particularly apt due to the members’ previous experiences. All of the members of the group have appeared on various reality TV shows, audition programs, or been part of other K-Pop acts. In this way the OMEGA in their name holds extra weight, as the members get another chance to showcase their skill. After debuting in 2021, the group recently debuted their first sub-unit, OX:N, consisting of members Jaehan, Xen, Jehyun, and Yechan on June 20th, 2025. Their mini-album, ‘N’ featured the title track ‘YOU‘.
In many ways, it is OMEGA X’s journey that holds so much appeal – with each member having diverse, unique and extensive histories in the genre, they each bring a refreshing yet sincere vibe to their music.
CONNECT WITH YECHAN & OMEGA X
X | Members’ X | YECHAN’s Instagram | OMEGA X Instagram | YouTube | TikTok
Stream “들었다놨다 (Up and Down)” on
Spotify & Apple Music
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