A certain recalcitrance has always been part of what makes Rosalía so compelling. As a teen-ager, she appeared on “Tú Sí Que Vales,” a talent-competition show on Spanish television; when one judge wasn’t impressed, she said, in Spanish, “I didn’t come here to accept criticism,” and the audience whooped in encouragement. Early in her career, she was sometimes celebrated for fleeing the strictures of flamenco music in order to find freedom on the dance floor, and on the charts. But dance floors and charts have their own rules, and one of the functions of an album as intense and expansive as “Lux” is to remind pop listeners of all the limits that they typically take for granted. The album has a notably wide dynamic range, which means that listeners who lean in during the quiet passages may find themselves blasted backward by the thunderous climaxes. In “De Madrugá,” she sings a few lines in Ukrainian to evoke the fervor of Olga of Kiev, the tenth-century ruler who massacred the tribe responsible for killing her husband. And for “Mio Cristo” she basically wrote herself an Italian aria and then learned to sing it, building to a glorious high B-flat that she hits and holds; we hear a quick snippet of Rosalía’s studio banter (“That’s going to be the energy, and then—”) before the orchestra cuts her off with the reverberant final note. Pop stars often talk about working hard, but Rosalía makes most of her peers seem lazy, and, indeed, any listener not inclined to embark upon a multilingual research project may end up feeling a bit lazy, too. Rosalía’s representatives asked journalists to listen to this album in the dark, while reading the lyrics on a screen—logically impossible, for most of us, but doubtless Rosalía herself could find a way.