A tough challenge is trying to transpose Brazilian popular music to a string quartet. This was the purpose of the Quarteto de Brasília on their second CD. Nineteen classics were arranged for that purpose by Ricardo Vasconcellos, who also played the eventual bass parts, while Maria Francisca Aquino played the piano. The approach chosen -- rather than a complete re-creation of each song in view of this peculiar purpose -- was to observe the genres in which they were written. The reason for this may be the classical obsession in following the "intention" of the composer, an essentialism contradicted every minute in popular music. Anyway, given this orientation, if the genre is naturally suitable for the quartet formation, the excellence of the performers, their cohesion as a group, and the competence of the arranger are enough to provide the listener with good realizations. This is the case for "Rosa" (Pixinguinha), for instance, in which the subtlety of the rhythm of the valse makes possible a flexible use of every instrument in a polyphony of enchanting melodies. More or less the same can be said of "Luíza" (Tom Jobim), "Eu Sei Que Vou Te Amar" (Tom Jobim/Vinícius de Moraes), "Gente Humilde" (Garoto/Vinícius de Moraes/Chico Buarque), "Laura" (João de Barro/Alcir Pires Vermelho), "Carinhoso" (Pixinguinha), and a couple of other songs. But when the subject is bossa nova, for instance, the group is at a disadvantage. Having to assign the cello to the chord root and in general the viola and the second violin to the complementary notes of the chord, the general movement becomes rigid, not to mention that the modern harmony of Brazilian music after the '40s is mistreated by this logistic limitation. And when a street band is emulated on "A Banda" (Chico Buarque), the results are on the verge of ridiculous. The work has its merits, mostly because of the acknowledged capability of the musicians and of Vasconcellos' knowledge of and experience in popular music, but it would profit from a completely different orientation, in the lines of a profound reformulation of the compositions' structures, as suggested by the inventive intros here realized for each song.