Ten years ago today, Swiss ethno-musicologist and music producer Marcel Cellier (1925-2013) passed away. He left behind a bright mark in the history of Bulgarian music in this country and around the world. Marcel Cellier and his wife Catherine devoted a large part of their lives to Bulgarian folklore - love that dates back to the middle of the 20th century, when they first heard Bulgarian folk songs broadcast on BNR. It was music that captivated them and linked their lives with "the mystery of Bulgarian voices", the archives of the BNR recall. This is the person who presented to the world the performances of the Ensemble for Folk Songs of the Bulgarian Radio, which became famous around the globe under the name "The Mystery of Bulgarian Voices".

Marcel Cellier began cooperation with the Bulgarian National Radio by purchasing recordings for a radio broadcast in Switzerland dedicated to Bulgarian choral singing. The 30-minute radio shows were broadcast once a month from 1960 to 1990. "The Mystery of the Bulgarian Voices," as Catherine Cellier called the show, became a trademark. In 1975, the first album under the title "The Mystery of Bulgarian Voices" emerged. The second album under the same title was awarded a "Grammy" in the category "Best Traditional Folk Recording" for 1989.

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