Aparecida" and "Mulher Brasileira". He also repurposed a tuning fork, a device traditionally used by musicians to maintain musical tuning among instruments; the singer instead stimulated it with his mouth to generate sounds that resembled a harmonica. For their part, Trio Mocotó attempted to develop a distinctive groove with a rhythm that would suit the rock or "iê-iê-iê" feel of Ben's guitar playing. The band played several percussion instruments, including the atabaque and bell plates. For "Charles Jr." and other tracks, Parahyba used the whistle of his sister's electric toy train as a horn instrument, breaking it in the process. String and horn sections were recorded and included in the final mix but went uncredited in the album's packaging. It credited C.B.D. in Rio de Janeiro and Scatena in São Paulo as the recording locations for Fôrça Bruta, which was named after the Portuguese for the phrase "brute force". According to Robert Leaver of Amoeba Music's international records department, "one can see a sly irony" in the title, considering the heightened political tension in dictatorial Brazil at the time and the gentle quality of Ben's music for the album. Musical style Fôrça Bruta has a pervasive sense of melancholy, according to Brazilian music scholar Pedro Alexandre Sanches. Songs that do not demonstrate this quality in their lyrics do so with their melodies, arrangements, and Ben's "devilish" guitar figures, with "Oba, Lá Vem Ela" and "Domênica Domingava" cited by Sanches as examples. He identifies each composition on the album as either a samba, samba lament, or "samba-banzo", which in his opinion gives the record an idiosyncratic sense of contrast. Greg Caz, a disc jockey specializing in Brazilian music, believes Fôrça Bruta possesses a melancholic, mysterious quality that departs from the carefree sensibility that had been the singer's trademark. He also observes a heightened progression in Ben's idiosyncratic guitar playing. Music journalist Jacob McKean finds it subtle and "stripped down" when compared to Ben's previous music, with his guitar more prominently featured, his vocals "more intimate", and a "somewhat crunchy, folksy tone" established by the opening songs "Oba, Lá Vem Ela" and "Zé Canjica". Songs such as the cuíca-driven "O Telefone Tocou Novamente" and "Zé Canjica", featuring a drum cadence, experiment with unconventional percussion arrangements, resulting in rhythmic contrasts between Trio Mocotó and Ben's instruments. This rhythmic direction departs from his earlier music's innovative "chacatum, chacatum" beat, which had become popular and