He was born in San Sebastián (Basque Country, Spain). He began studying harmony, piano and trumpet at San Sebastián School of Music. When he was eighteen years old, he moved to London, where he studied piano for six years at the Guildhall School of Music, and graduated. His teachers were Norman Beedie, James Gibb and Edith Vogel, from whom he inherited a beautiful legato and a deep sense of singing.

As a composer, he has written music for different chamber groups and for piano (three “Quartets” for string quartet, “Elegy” for string chamber orchestra, “Danza of the Birds” for two clarinets and cello, “Fantasie”, “24 Preludes”, “Miniatures” and “Woodland Scenes” for piano solo, “Galerna”, a symphonic poem for orchestra, etc). He has also composed a Piano Concerto and “Lamiaren Heriotza” for string trio, harp and flute, which was performed on May 2005 by members of the Tenerife Symphonic Orchestra in Tenerife. In 2005, he played his own piano music at Sigyn Hall in Turku, Finland; at Chillida Leku, during “Quincena Musical” of San Sebastián; and at Juan March Foundation, Madrid, for a series of concerts about Spanish piano music. During the same series, the pianist Gustavo Díaz-Jerez performed for the first time his work “Escenas Selváticas”. In August 2007, his piece “Epilogue” for harp solo, was played for the first time. He was commissioned to compose this piece by “Quincena Musical” of San Sebastián, to pay tribute to the famous harpist Nicanor Zabaleta. In 2009, the piano duo Aristizabal-Barandiaran premiered at Eresbil, the Basque Music Archive, his work “Scenes of Power”. At the same concert series, his Piano and Wind Quintet was premiered by the Enoff Quintet, with the composer himself at the piano. During the 2009 “Quincena Musical” of San Sebastián, the Kratos Duo premiered his sonata “Piacell” for cello and piano. In 2010 Rosa Torres Pardo performed two piano pieces in a homage recital to the poet Luis Rosales at the Teatro Español in Madrid. In December 2013 the Bretón Quartet premiered his third string quartet in the Ciclo Alicante organized by the CNDM, which was performed again during the Quincena Musical de San Sebastián in August 2015, and in November 2015 in a cycle about the spanish string quartet organized by Cervantes Institut in Munich. The fourth string quartet was premiered at the Contemporary Music Cycle during the Quincena Musical de San Sebastián in 2016. His Oboe Quartet, dedicated to the great oboist Juan Manuel González Lumbreras, was premiered in April 2015 in the Orquesta de Euskadi Hall by Irauli Quartet with Javier Lecumberri as soloist. Gustavo Díaz-Jerez premiered his new piano piece in November 2015 in the Real Casino de Tenerife. In May 2016, the Basque National Orquestra, together with the Coral Andra Mari, premiered "Balea" for soprano, baritone, choir and orchestra at Musikaste. The Sax Ensemble premiered his "Cervanres' Portraits" for sax quartet and piano at the San Fernando Royal Academy of Fine Arts in Madrid in December 2016.

Among his next premieres is "Euskal Balezaleak" about the history of the Basque whalers, for wind quintet, percussion and choir, with members of the ORTVE and Martín Llade as narrator. Also in June 2017, his string trio "Poetic Enigmas" will be premiered at the Korean Cultural Festival in Madrid by the Trio Laso.

As a soloist, Gabriel Loidi has performed recitals in Spain, England, France and Finland. In March 2003 he played one recital of the Piano Fantasies Series at Juan March Foundation in Madrid, which was broadcast live by the Spanish National Radio.In 2005 he played a recital in Sigyn Hall in Turku, Finland and at Chillida Leku during the “Quincena Musical de San Sebastián”. In January 2006 he played Bach’s Goldberg Variations at Prieuré le Mesnil Saint-Martin, France. With regard to chamber music, he has performed duos with the spanish mezzosoprano Marina Pardo and the american violinist Ida Bieler. He has played the six Sonatas for violin and cembalo by Bach with Ida Bieler at the 2002 and 2003 editions of Ezcaray Music Festival. He has also recorded for the Spanish National Radio music for two pianos with Rosa Torres-Pardo. He founded Ezcaray Music Festival at Ezcaray (La Rioja), and managed it until 2003.

He has worked as a piano teacher from 1987 in different Music Schools at San Sebastián, London and Madrid. He collaborated with COPE Radio of Guipúzcoa to create a “Guide to listening”. He has also offered several conference-concerts, and a summer course for Carlos III University of Madrid, called “Music: Thought and Emotion”. He gave piano master classes in Madrid, and chamber music master classes at Turku Conservatory, Finland, in 2004, 2005 and 2006 as a part of an Erasmus exchange. From 2005, he has provided chamber music tuition for teachers in Palencia, Cáceres and Soria Professional Conservatories. In 2013 he collaborated with Mikaela Vergara on a radio programme about music, thought, sentiment and emotion. From 2002, he has been working as a chamber music teacher at Musikene, the Basque Country’s Higher School of Music.