- Santiago A. Calvo Ramos: vocals, lapsteel, reed organ, overdubs
- José Manuel Domínguez Roldán: synthesizers, piano, melodica, backing vocals, lead vocals on "eleven" and "rondpoint"
- Guillermo López González: acoustic and electric guitars, ukelele, melodica, backing vocals, lead vocals on "first day of spring".
- Sergio B. Negrín Dastis: spanish guitar on "At the piano workshop"
The CD contains two independent mini-albums, "On the eighth floor" (songs 1 to 7) and "At the piano workshop" (songs 8 to 14) recorded at separate sessions but sharing the same approach: to record songs without bass or drums, in a simplified manner, without much post-production work and with a strong sense of the locations they were recorded in.