They formed a business relationship and set up two classical music record labels, both named Harmonia Mundi.The two labels shared similar aims and specialised in recordings of Early and Baroque music, with an emphasis on scholarly, historically informed performance and high-quality sound and production values.Ruby retired in 1992 and Coutaz tried unsuccessfully to buy the German record label and Deutsche Harmonia Mundi was wholly acquired by BMG.[8] Noted artists and ensembles who have recorded with Harmonia Mundi have included Maya Youssef,[9] René Jacobs, Dominique Visse, William Christie, Alfred Deller, Andreas Scholl, Philippe Herreweghe, Maurice Steger, Alexander Melnikov, Isabelle Faust, Jean-Guihen Queyras, Kent Nagano, Samuel Hasselhorn, Raphaël Pichon, Amandine Beyer, Freiburger Barockorchester, les Siècles, Akademie für Alte Musik Berlin and Collegium Vocale.[6] Harmonia Mundi also issues recordings under a number of subsidiary labels such as Ambronay, Discograph, Le Chant du Monde and World Village.