Like other K-pop sensations, Big Ocean sings, raps, dances and attracts swooning fans. But this new group’s meteoric rise is fueled by a skill no other boy band boasts: signing.

The band members — Lee Chan-yeon, 27, Park Hyun-jin, 25, and Kim Ji-seok, 22 — are all deaf or hard of hearing. They use the latest audio technology to help make their music, coordinate their choreography with flashing metronomes and vibrating watches, and incorporate Korean Sign Language into videos and performances.

“Just like divers rely on signs to communicate underwater, we use sign language to convey meaning where sound alone might fall short,” Mr. Lee said. “For us, KSL is not just an element — it’s the heart of our performance.”

The group released their debut single, “Glow,” last year, on Korea’s Day of People with Disabilities, and did their first televised performance incorporating KSL, generating local buzz that reverberated beyond national borders. Soon after, they followed up with “Blow,” a single heavy on English lyrics and American Sign Language.

In September, they were named Billboard’s rookies of the month, and recently they made the Forbes 30 Under 30 Asia Entertainment & Sports List. This month, the band performed at an anime festival in Brazil and at a United Nations tech event in Switzerland, before touring Europe for the second time since spring. Their first American tour starts in late July.

Big Ocean now has 995,000 followers on Instagram and more than 696,000 on TikTok. Fans, who call themselves “Pados” after the Korean word for wave, are devoted, and many are learning sign languages from the band, which makes numerous tutorials.