A Brief History of K-POP: sub-units

The idea of "super groups" is not a new one. As early as the 1960s, groups like Crosby, Stills, Nash, and Young were being formed and received with great success. In K-Pop, this idea has morphed into what are called "sub-units".

Over the past 10 years or so, K-Pop has seen a surge of groups creating "sub-units" from larger groups. A sub-unit is a mini-group formed with members from the lineup of a larger group. The newly-formed “mini-group” will then have separate music releases while being promoted under the new entity with ties to the original, whole group lineup.

Many K-POP fans love this trend, saying it has produced some of the best acts and songs in the genre. Sub-units, some argue, allow K-Pop idols to explore genres and concepts that are different from what they typically do within the larger group.

Here’s a little look into some of the types of sub-units that exist in this genre and how they operate—from permanent sub-units within large groups, to company project groups, to temporary sub-units that are formed while other group members are on hiatus.

SM Entertainment was the first company to debut an official sub-unit in K-Pop, Super Junior-K.R.Y. They debuted in November of 2006 on the soundtrack for a TV drama called “The One I Love”. Following the success of this first release, the trio released other soundtracks which were also hugely successful. Skipping ahead to May of 2020, the sub-unit released their first Korean album “When We Were Us”.

During this time, a number of other Super Junior sub-units were formed, with each sub-unit focusing on a different approach to K-Pop: Super Junior-T (2007) specializing in Korean trot, Super Junior-M performing in Mandarin, Super Junior-Happy (2008) with bubblegum pop, and Super Junior-D&E (2011) and Super Junior K.R.Y with R&B-style ballads. Fans of the concept see it as an opportunity for group members to explore diverse styles/approaches with unique member lineups.

With the huge success of Super Junior’s sub-units, many other acts have taken up the trend. Arguably one of the most impactful sub-units is Orange Caramel who made their debut as a sub-unit in June of 2010 with the single “Magic Girl.”

Consisting of three members from Pledis Entertainment’s girl group AFTER SCHOOL, Raina, Nana, and Lizzy, Orange Caramel saw commercial success with their debut album “The First Mini Album”. The sub-unit’s 2014 release, Catallena went viral and entered charts both in Korea and internationally.

Orange Caramel’s third single was included in Billboard’s Top 100 Greatest K-Pop Songs of the 2010s at No. 20.

PERMANENT SUB-UNITS WITHIN LARGE GROUPS
Groups with 10 or more members may operate under a sub-unit system with permanent fixtures within the collective group.

For example, SEVENTEEN is a 13-member group with three permanent sub-units that highlight specific genres: hip-hop unit, vocal unit, and performance unit. Despite being separate groups with different approaches to their sound, the sub-units’ still release each album under the collective group’s name. SEVENTEEN’s first sub-unit was BSS or 부석순 (BooSeokSoon) who debuted in March of 2018 with the release of their digital single “Just do it”.

Other groups with permanent sub-units include NCT (Neo Culture Technology) and LOONA who’s debut was a project that spanned over two years, featuring individual as well as sub-unit releases. In the case of LOONA, three sub-units were released with music video releases as well as physical album releases that eventually led to the debut of the collective group in 2018. This is an interesting, reverse-engineered format that has set the stage for a wide variety of possibilities for both existing and upcoming groups. It will interesting to see where this refinement leads.

In 2017, four out of five members of Pledis Entertainment’s NU’EST joined the boy group survival show Produce 101 Season 2. With Minhyun making the final lineup of the show and becoming a member of the temporary group WANNA ONE, the remaining four members formed NU’EST W. The sub-unit debuted in July of 2017 with “WHERE YOU AT,” earning the group their first win after five years since debut. With the “W” in their name standing for “wait,” NU’EST W carried on promotions as a sub-unit until they disbanded in December of 2018 following Minhyun’s return to the group.

After over a year with no activity and in interim of PRISTIN member Kyla’s hiatus, Pledis Entertainment announced the debut of PRISTIN V. The lineup of five members from the original group released a single album titled Like a V featuring title track “Get It” in May of 2018.

As things were looking up for a possible full group comeback, it was announced a year later by the company that PRISTIN had disbanded following the contract termination of seven out of 10 members.

TEMPORARY SUB-UNITS
In the absence of a group’s members, whether due to military service or the pursuit of other project commitments, temporary sub-units can also be formed. In 2012, for example, Girls’ Generation went on hiatus with the majority of members focusing on individual activities. The sub-unit, TTS (TaeTiSeo) was formed with Taeyeon, Tiffany, and Seohyun who released an EP called "Twinkle". This became the first album by a Korean artist to rank No.1 on the Billboard World Albums Chart.

COMPANY SUB-UNIT PROJECTS
At times, artists from the same company will partner up for projects by forming what may be referred to as "company sub-units". Like the backward design of LOONA, cross-group collaborations like this have been formed by artists in companies such as SM Entertainment, YG Entertainment, and CUBE Entertainment.

YG Entertainment’s cross-group sub-units tend to be formed as duos such as HI SIHYUN which consists of LEE HI and LEE SUHYUN and MOBB, made up of WINNER’s MINO and iKON’s BOBBY.

In the world of K-Pop, SM Entertainment is a giant. This incredibly innovative and successful company is often at the leading edge of K-Pop developments. In terms of sub-units, SM Entertainment has created cross-group sub-units from groups within their company like Younique Unit with members from Girls’ Generation, Super Junior, SHINee, and EXO, as well as collaborating with Woollim Entertainment to form the cross-company sub-unit ToHeart.

While this post has ended up longer than I had originally planned, there are many other sub-units in K-Pop that have not been mentioned here. Still, it seems for anyone interested in the question of where music is today, and it is headed in this age of AI-created music, virtual concerts, and legacy bands, sub-units are a fascinating development that will almost certainly spread beyond it's K-Pop roots. It will be amazing to see where this idea spreads too and how it evolves over time.

Keep an eye out on YouTube for upcoming episodes of "Our Mind on Music" discussing past, present, and future music!

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What is duetting? (BlackPink: Shutdown):