“Bloque 6” (1968), by Juan Carlos Calderón, is a landmark recording in the history of modern jazz in Spain, markedly different from the albums Calderón would record just a few years later under the influence of funk, disco music, and even flamenco. Juan Carlos Calderón enjoyed a long and successful career,  composing and arranging some of the most iconic songs by Spanish artists such as Joan Manuel Serrat, Mocedades, and Ana Belén, among many others. However, his musical beginnings were closely tied to the world of jazz. His training as a pianist and the restless, adventurous spirit he shared with his brothers—alongside whom he opened one of Spain’s first jazz clubs, a venue that welcomed many of the world’s leading jazz figures—shaped the early stages of his career and led him into the jazz scene.

His recording debut came in 1968 with the release of “Juan Carlos Calderón presenta a Juan Carlos Calderón”, followed a few months later by “Bloque 6.” For the recording of this album, he assembled a group of prominent Spanish jazz musicians, including Pedro Iturralde, Vlady Bas, and Pepe Nieto. The  repertoire combines original compositions, such as the outstanding ‘Sambando,’ with interpretations of works by Miles Davis, Thelonious Monk, and Oliver Nelson. The album’s sound invites comparison with Nelson’s celebrated “The Blues and the Abstract Truth” period, reflecting strong hard bop and modal jazz  influences. In 1969, the album was awarded Best International Jazz Album of the Year in the United States, and years later it was reissued on CD by the prestigious Blue Note label.