B1A4 Returns With Synth Ballad 'Lonely,' Full Album 'Who Am I'

B1A4, "Lonely" MV

The K-pop quintet blends '80s synths and Southern hip-hop style for the lead single off its sophomore album.

After their One Direction-meets-hip-hop single "What's Happening?" gave K-pop boy band B1A4 their highest-charting single on the K-Pop Hot 100 yet (No. 13), the boys have followed up with their second full-length Korean album "Who Am I." The release -- which marks an impressive feat for the band for having less than four years under its belt -- is led by an ambitious ballad single, "Lonely."

For the new song, the quintet presents a complex arrangement of '80s-inspired synths mixed with ornamentations of Southern hip-hop, all sang in a melancholic, ballad-style delivery.

With its recent singles, B1A4 has blended seemingly disparate genres -- like woozy EDM and acoustic rock ("Tried to Walk") or bubblegum pop and beat-driven hip-hop ("What's Happening?"). But "Lonely" may very well be their most successful result yet.

Along with "Lonely," B1A4 dropped new album "Who Am I" on Jan. 13. The 12-track disc was previewed by a highlight medley (below) released on the boys' YouTube channel four days before the album. To further promote the album, the band announced a "hometown tour," which will see the boys perform in their hometowns across South Korea. The trek kicks off in March.