In 1968 Eduardo Llerenas, at that time studying for his PhD in biophysics, began to travel all over Mexico with a group of friends, listening to countless traditional musicians in villages, ranchos and towns all over Mexico.

They developed a knowledge and a passion for the different styles of traditional music known in Mexico as son which they heard in the parties, homes and festivals of each of the regions that they visited.

Three years later, Llerenas, together with musician Baruj Lieberman and the maths professor and electronic engineer Enrique Ramírez de Arellano, began to make professional recordings of the most outstanding musicians that they heard. Inspired by the beauty of the music, they recorded the anonymous masters whose talent had not previously been recognized outside their own region. Despite being 'amateurs', the combination of a scientific training and a passion for the music ensured that the recordings were made to very high technical standards.