Diphonon Duo is a viola and accordion duo formed by the Greek viola player Michael Iskas and Iñigo Mikeleiz Berrade, accordionist from Navarra (Spain). Michael and Iñigo met in 2015 during their Masters of Arts studies at the Royal Academy of Music and after discovering they share common musical interests, they decided to establish this ensemble.

The word "Diphonon" means in Greek "two voices".

The combination of accordion and viola, bow and bellows, is an unusual duo, however the two instruments have more similarities than we think, since both are able to sustain sound for long time and vary its color and intensity. For string players, this possibility is a very interesting item to explore. The great cello player Mstislav Rostropovich said that "If cellists want to discover the possibilities of the cello, they should play with accordion and not piano".

The repertoire performed by Diphonon Duo reaches different styles and ages. From original works for the duo, to transcriptions of baroque and classical music. The duo involve the audience in journey through time and space, from the 17th century, with the great British composer Henry Purcell, to the present day, being able to appreciate contemporary but very stylistically different pieces from distant countries such as Argentina, Denmark, Spain, the eastern Mediterranean Sea and Japan. Many of the works performed by Diphonon Duo reflect traditional elements of various regions of the world (for example dances, rhythms, songs). The ensemble’s repertoire includes composers such as Benjamin Britten, Astor Piazzolla, Graciane Finzi, Martin Lohse, Arvo Pärt, Gorka Hermosa, J.S.Bach and many others. As the repertoire for this combination of instruments is quite limited, during the last year some composers have offered to create contemporary pieces for Diphonon Duo, specifically written for accordion and viola.

Diphonon Duo performs in various venues in London, UK and Spain such as the Wigmore Hall, St Martin in-the-fields, St James's Piccadilly, Royal Academy of Music, British Museum, Bristol Beacon, Seamus Heaney Home Place (Bellaghy, Northern Ireland), Civican Centre (Pamplona, Spain), Teatro Cajasol (Seville), Biblioteca Rectorat de Lleida, et al.

During the course 2017-18 they were appointed as Wigmore Hall Learning Ensemble, being regular collaborators since then, and from 2019 they are members of Live Music Now, an organization that works with a very diverse range of people that rarely, if ever, have the opportunity to experience live music.

The duo has received coaching and guidance from eminent musicians such as accordion professor Owen Murray, Mario Stefano Pietrodarchi, Mie Miki and Bjarke Mogensen (accordionists), viola professors James Sleigh and Roger Chase and violist Garth Knox. This has shaped the stylistic perception of the ensemble depending always on the unique character of each composition.