The words “limitless” and “rotational” are central to the existence of the global K-pop boy group, NCT. This means existing and new members can perform in an unlimited variety of fixed and temporary subunit line-ups. The combination of NCT members Taeil and Haechan’s voices has been a recipe for success across the group’s discography. Through informal performances and their self-composed song, “Love Sign,” fans got a taste of what a duet would be like with the two vocalists. The NCT system offers limitless possibilities for music releases outside the current three fixed subunits. This article explores why Taeil and Haechan, also known as “Sun & Moon,” could be a sweet-sounding subunit.
Several NCT members have released duets across the years, often under NCT U, a subunit where any member combination is possible. A popular duet song was the flirtatious “Baby Don’t Stop” from NCT 2018 Empathy, performed by Taeyong and Ten. NCT members have also released official soundtracks (OSTs) as NCT U pairs, including “New Dream,” an OST sung by Taeil and Jaehyun in 2018 for the web series Dokgo Rewind. There are also stand-alone digital singles, such as “Maniac” (Prod. RYAN JHUN), which was sung by Doyoung and Haechan in 2021.
The NCT subunit, WayV, had a more formal rollout of digital duet singles in 2021, with Kun and Xiaojun’s “Back To You,” followed by Ten and YangYang’s “Low Low.” Through these duets, fans saw the WayV members explore different sides of music and performance compared to their larger subunits.
Outside of official releases, NCT members have made music together in pairs through unofficial self-composed songs. Taeyong and Mark, Johnny and Mark, and Taeil and Haechan have all shared or performed songs they have worked on together. The recently launched “NCT Lab” project also provides a platform for NCT members to share unit songs outside of album activities.
Sun & Moon
The oldest and youngest members of NCT 127 are often referred to as “Sun & Moon.” This came from Taeil’s surname, Moon, and the meaning behind Haechan’s name, “full sun.” Despite having the largest age gap in NCT 127, they are known for their close friendship. The chemistry and comedic timing between the two was captured in the Welcome To Sun & Moon interview show, which featured NCT members behind the scenes of NCT 2020 Resonance. Fans have also expressed wanting to see music content from the “Sun & Moon” duo.
Throughout NCT Discography
The compatibility of Taeil and Haechan’s vocal colors is noticeable across NCT’s discography with their harmonies and adlibs. The introduction of the R&B pop track, “Love Song,” with Taeil starting the song smoothly followed by Haechan is one of many examples of producers utilizing the vocalists together. These performances have piqued an interest in a subunit from fans.
Since the group’s debut with “Fire Truck,” Taeil and Haechan’s voices have become a signature part of NCT 127’s iconic bridges. In this track, Haechan suavely started the bridge and Taeil powerfully brought the section to a close. Other notable examples include the climatic bridges of “Superhuman” and “Simon Says.” With the strong results of Taeil and Haechan’s voices combined in NCT’s discography, it would be exciting to see these two vocalists shine as a duo.
Fans have gotten a taste of Taeil and Haechan duets through unofficial covers. In Taeil’s Masked Singer Practice Journal, Haechan joined Taeil to rehearse Yerin Baek’s “Across the Universe” in preparation for his participation in King of Mask Singer.
With covers gaining positive feedback, there is fan interest to hear more covers and original duets between the vocalists.
More recently, Taeil and Haechan shared “Love Sign.” The unreleased self-composed duet was made with songwriter, producer, and one of Haechan’s musical inspirations, DEEZ. Described by Haechan as “very sexy and sad at the same time,” the yearning R&B song was performed during NCT 127’s 2021 NEO CITY : SEOUL – THE LINK concert. “Love Sign” showed off the singers’ abilities as both musicians and performers. Haechan revealed, “the highlight of the song is probably the way Taeil and I harmonize our voices.” Another standout moment in the performance was when Haechan performed a self-choreographed solo dance, while Taeil played on a synthesizer keyboard. For the performance, Haechan disclosed both Taeil and Haechan had “a role to act out” to convey “the feeling of ‘Sun & Moon.’” He explained, “Taeil was doing performance actively on a stage and I was more ‘expressive’ with dance.” With these specific roles during the “Love Sign” performance, the continuation of the “Sun & Moon” theme through music and performance could be a fascinating concept.
The song received a positive reception from fans who eagerly requested for an official studio version to be released, and more music between the duo. The unreleased track also gained attention on Genius Korea, a community project for lyrics, romanization, and English translations of Korean music on the Genius website. “Love Sign” reached #5 on the K-R&B chart, as fans eagerly looked up the lyrics.
The behind the scenes footage of the “Love Sign” recording process highlighted Taeil and Haechan’s teamwork. Taeil admitted the song was “very difficult” to sing. They were able to produce an amazing final result, as they monitored and advised each other on technique, tone, and dynamics.The strong working dynamic between Taeil and Haechan did not go unnoticed by fans. Both Taeil and Haechan proudly spoke about “Love Sign” as an important moment for them as artists. Speaking during concert rehearsals, Taeil shared “although we made it, we get impressed by how good it is.” For Haechan, “Love Sign” was also a step in his goal to become a singer-songwriter, and to write more similar songs. “I want to write a lot of songs like “Love Sign,” he told a fan.
With “Love Sign” as one of Taeil and Haechan’s first examples of a self-composed song shared with fans, NCTzens, NCT fans, anticipate more from them as a duet and singer-songwriters. Like the NCT system itself, the potential for different subunit combinations is limitless!
You can read more about “Love Sign” and the other NEO CITY : SEOUL – THE LINK performances here.
Translations by Jin or linked sources.