Quarteto Em Cy started as a family affair. Cyva, Cynara, Cylene, and Cybele Sarmento grew up singing together in Salvador, and when they moved to Rio de Janeiro in the mid-1960s they brought a sense of blend that only sisters who have been harmonizing since childhood can really pull off. The name is a small joke made real: four voices, all starting with Cy, locked into one instrument.

What they do is not flashy. It is precise. Listen to how they phrase a lyric together, how the harmonies stack without anyone pushing too hard for the lead, and you start to understand why so many Brazilian songwriters wanted them singing their material. Vinicius de Moraes and Toquinho both worked with them, and that pairing made sense — this was a group that treated a song's structure with the same respect a good arranger would, never overselling the melody, always serving it.

Their early records sit right at the crossing point of bossa nova's cool reserve and the more harmonically ambitious vocal jazz coming out of groups like Lambert, Hendricks and Ross or The Manhattan Transfer, except filtered through a specifically Brazilian sense of rhythm and lyricism. You hear sophisticated chord voicings, but you also hear samba in the body of the thing, which keeps it from ever feeling academic.

What makes them worth seeking out, decades later, is durability. Lineups changed, members came and went, but the group kept working, kept recording, kept finding new songwriters to interpret. For anyone who thinks Brazilian vocal music begins and ends with bossa nova's gentle whisper, Quarteto Em Cy is a good corrective — four voices that could whisper just as easily as they could swing hard, and who built a career on knowing exactly which to do and when.