Diego is the Principal Horn of the London Symphony Orchestra, which he joined in 2023, after holding both the 3rd horn and Principal chairs at the Philharmonia. In 2026 he served as Principal Horn of the San Francisco Symphony after his appointment by MD Esa-Pekka Salonen. He has also played as guest principal horn with the London Philharmonic and Royal Philharmonic Orchestras as well as the Orquesta Sinfónica de Castilla y León, City of Birmingham Symphony Orchestra, BBC Philharmonic and BBC Scottish Symphony Orchestra. He has also been principal horn of the Gustav Mahler Youth Orchestra in 2017.

Diego was born in Valladolid, Spain, where he started playing the horn at age 8 under the guidance of Carlos Balaguer. He continued his studies in the Reina Sofia School of Music in Madrid with Radovan Vlatković and Rodolfo Epelde before joining the Royal College of Music under Jeff Bryant, Timothy Jones and Nigel Black.

Besides orchestral activity, Diego has appeared as a soloist in Schumann’s Konzertstück with the Philharmonia conducted by Santtu-Matias Rouvali and Helmut Lachenmann’s My Melodies with the LSO conducted by Ilan Volkov. He is a member of the London Horn Quartet and often plays chamber music with the LSO and Philharmonia Winds, and the Wigmore Soloists, with artists such as Michael Collins, Isabelle van Keulen and Benjamin Gilmore. He is also an active session musician, having played in several films, pop albums and videogames with the LSO, Isobel Griffiths Ltd. and COOL Music. He can be heard in soundtracks such as Wicked (2025), Jurassic World Rebirth, Napoleon and Mission Imposible Death Reckoning, also in recordings featuring artists such as Rosalía, Ariana Grande, Neil Diamond or Barbra Streisand.

Since September 2022, Diego has been a Professor at the Royal College of Music.

Diego plays on a Paxman 20M french horn.

Photo: ©Kira Doherty, 2023