He received his PhD at the Complutense University. He worked for many prestigious cultural institutions in Spain, such as the Cervantes Institute or Madrid's opera house Teatro Real. In 2014, Carmena joined the European Film Philharmonic Institute. As its creative director, he is responsible for developing the musical dramaturgy and visual design of live music concerts and also for contributing to the company's artistic strategy together with founders Beate Warkentien and Frank Strobel. Carmena writes about film music for numerous books and magazines, delivers lectures and workshops and curates independent live music shows for the festival Veranos de la Villa in Madrid as dramaturge and artistic advisor.