“Power ballad.” The phrase sounds like an oxymoron. Rather, it’s shorthand for the type of song that has, over time, deftly avoided definition. To wit, an anthology titled “The Very Best of Power ...

Ballads have returned. The slow, emotional sensibilities of ballads, which had been overshadowed by the dominance of K-pop dance tracks, are showing signs of revival. As of the 21st, ballad-style ...