Sometimes the best ballads are simple.

Like the Beatles' "Hello Goodbye" or Bobby Hebb's "Sunny" before him, Yoo Seung Woo takes a simple sentiment and plays it up for full dramatic effect in his new single "Hello," released on May 8.

The song is from Yoo Seung Woo's album "The First Picnic" released the same day.

Featuring the jazzy sound of major seven chords and a rhythm section that sounds like they just stepped off the stage of New York City's Blue Note jazz club, the song has a laid-back vibe, without becoming boring.

Often when one hears the opening chords of a K-pop ballad, the listener knows what to expect: a sleepy, sentimental composition that sounds as though you have heard it a million time before.

With sounds like brushes on the snare drum or an extended harmonica solo, the producer of Yoo Seung Woo's "Hello" dials in a sonic palette not frequently heard in mainstream Korean music.

The lyrics and the former "Superstar K4" contestant's relaxed delivery help to create a mood in the song that is unforced and whimsical, like a stroll on a warm summer evening, with the perfect breeze.

Sometimes a simple lyrical hook, like Yoo's "hello marshmallow," is all you need to create heartwarming pop.

Also employing a slightly retro feel, the music video for "Hello" foregoes the spastic jump cuts ubiquitous with modern pop music videos for long, static single shots that give "Hello" a cinematic feel.

Instead of bludgeoning the viewer with endless quick edits, the director of the "Hello" video instead employs slow close-ups on Yoo Seung Woo and his band.

The overall effect is downright charming.

At age 19, Yoo has an impressive self-awareness, which has allowed him to create a song that is both popular ("Hello" debuted at number nine this week on the Billboard K-pop Hot 100), but also inventive.

Writing an acoustic song that is relaxed, but not coma inducing, catchy but not cheesy, accessible but not over-produced, is no simple piece of work.

Somehow, this promising young performer makes it look easy.

Check out the music video for Yoo Seung Woo's new single "Hello" of the album "The First Picnic" RIGHT HERE