EGREM/Areito (cover drawing: Posada, design: Pablo Labañino, production: Pablo Menéndez, musical directors: Leo Brouwer, Juan Márquez, Armando Guerra), "Grupo de Experimentación Sonora ICAIC," late 1960s. Offset print, vinyl record LP.

This vinyl record represents one of the most significant documents of Cuban revolutionary musical experimentation. The Grupo de Experimentación Sonora (Sound Experimentation Group) was founded at ICAIC (Instituto Cubano del Arte e Industria Cinematográficos) to create innovative soundtracks for Cuban cinema, becoming an incubator for what would emerge as the Nueva Trova movement that defined revolutionary Cuban music.

The cover design by Pablo Labañino incorporates drawing by Posada, delivering powerful visual impact through stark contrast and provocative imagery. A skeletal or emaciated figure raises a revolver overhead in a gesture of defiance, rendered in expressive purple-blue brushwork against a vibrant yellow background surrounded by bold purple borders. The enormous "33" dominating the composition references the record's 33 RPM speed while suggesting revolutionary dates or numerical symbolism. This raw, confrontational aesthetic captures the experimental and politically charged atmosphere of late 1960s Cuban culture, while the reference to Posada invokes the Mexican printmaker José Guadalupe Posada's revolutionary graphic traditions.

Under the general and musical direction of composer Leo Brouwer (with co-directors Juan Márquez and Armando Guerra), this ensemble brought together musicians who would become legendary figures in Cuban music: Pablo Milanés, Silvio Rodríguez, Noel Nicola, Sara González, Sergio Vitier, and Eduardo Ramos. The group members played multiple instruments and composed collaboratively, creating a laboratory for musical innovation.

The recording includes striking experimental pieces: "Eramos" with text by José Martí and music by Pablo Milanés, "Salgo de Casa" by Eduardo Ramos, "El Bala" by Pablo Milanés, "Sondeando" by Eduardo Ramos, "El Viejo Obrero" by Silvio Rodríguez, and "Canción del Constructor" by Pablo Milanés. Additional collaborators included Amado del Rosario on electric oboe and various wind and brass instrumentalists. Recorded at ICAIC studios with recording by Jerónimo Labrada, Ricardo Istueta, and Germinal Hernández, with illustration by Posada, design by Pablo Labañino, and production by Pablo Menéndez, this album was produced and distributed by EGREM on their Areito label.