Os Cariocas were one of the great vocal groups of the pre-bossa nova "radio singers" era... Led by Ismael Neto and Severino Filho, Os Cariocas developed a smooth, complex harmony style that became the model for later groups such as MPB4 and Quarteto Em Cy... Neto's recordings with the band were made in the 78 era; their first full album came after his death in 1956. Here's a quick look at the group's work...
Os Cariocas "Os Cariocas A Ismael Neto" (Columbia, 1957)
This early album (their first LP?) was an homage to the group's bandleader, Ismael Neto, who died a year earlier. His brother, Severino Filho, became the band's guiding force afterwards. The songs are all Neto originals, and the performances are uniformly over-the-top. Glee club vocals gone mad, with arrangements that range from staid to utterly outlandish. I think this primarily qualifies as kitsch, but these guys certainly had their fans, and they were quite a tight vocal group. This is, generally speaking, the inspiration for the vocals groups of the '60s, such as Quarteto Em Cy and the MPB4.
Severino Filho "Rio De Janeiro, Gosto De Voce" (Polydor, 1958)
A "solo" set by Severino Filho, with backing on a few tracks by Os Cariocas...
Os Cariocas "A Bossa Dos Cariocas" (Philips, 1963)
This perky vocal quartet was known as the greatest of the post-WWII vocal groups, and was the model for the bossa-era bands such as the gals in Quarteto Em Cy and their male counterpart, the MPB-4. Unlike their successors, Os Cariocas were not hopelessly saccharine, nor were their arrangements completely ludicrous. Sure, their Four Freshman-ish versions of various bossa nova standards are somewhat silly, but in an innocuous kinda way. These early '60s recordings were made well past the group's 1950s glory days, when it was still led by the famed arranger, Ismael Neto. Although these are not immortal recordings, this is certainly worth checking out. For more info, check out the group's website, which has an extensive historical section (in Portuguese).
Os Cariocas "Mais Bossa Com Os Cariocas" (Philips, 1963)
Os Cariocas "De Quatrocentas Bossas" (Philips, 1965)
Mainly for nostalgia-driven fans. Some bright, big, sometimes brassy orchestrations frame their too-smooth vocals. This really doesn't appeal to me: it's too easy-listeningish, even with the mildly adventurous touches in the arrangements. Just not my bag. Although I'm sure there are plenty of others out there who would really dig it. Includes compositions by Carlos Lyra, Roberto Menescal, Marcos Valle, Ronaldo Boscoli and other younger writers, as well as chestnuts from Joao de Barro and other samba-cancao composers.
Os Cariocas "Reconquistar" (Warner, 1992)
This "comeback" album features guest appearances by Guliherme Arantes, Joao Bosco, Ivan Lins, Tom Jobim and Caetano Veloso...
Os Cariocas "Os Cariocas Com Bossa" (Albatroz, 2007)
Os Cariocas "A Bossa Brasileira" (Albatroz)
Os Cariocas "Os Classicos Cariocas" (Albatroz)
Os Cariocas "Bossa Carioca" (Sony, 2006)
Os Cariocas "Mestres De MPB" (Warner, 1997)
Os Cariocas "e-Collection: Sucessos + Raridades" (Warner, 2001)
A 2-CD set with rare tracks and hits.
Os Cariocas "Serie Sem Limite" (Universal, 2002)
Os Cariocas "Pure Bossa Nova" (Verve, 2007)