The Choir was set up by Constantinos Angelidis and his associates in late 2005, its aim being the study and promotion of Byzantine music, as that has come down to us today. It has appeared at the Athens Concert Hall (five concerts in collaboration with the Hellenic Radio and Television Music Ensembles, etc.) and in various cities in Greece, such as Tripoli, Mytilene, Patra, Hydra, Thessaloniki, etc. Outside Greece, it has appeared at international music festivals and has given concerts in various countries, such as Poland, Romania, Cyprus, Turkey, Sweden, France, Great Britain, Portugal, Austria, Lebanon, the Czech Republic, Russia, and Morocco (to mark the centenary of the foundation of the Kingdom of Morocco - in collaboration with the 'Ensemble Al-Kindi' and the conductor Julien Jâlal Eddine Weiss), in Germany (to mark the 850th anniversary of the founding of the city of Munich), etc. An important part of the Choir's activities is taking part in acts of worship, consecrations of new churches, solemn episcopal Vespers, and Divine Liturgies, lengthy vigils, etc. Particularly notable here are the Patriarchal Liturgies with the Ecumenical Patriarch Bartholomaios at Aghiasos on Lesvos (August 2006), in the Church of St John the Baptist at Kirkintzes (Şirince) near Ephesus, and in the Church of St Photeine, Smyrna (Turkey) (March 2008), the Patriarchal Liturgy with Cyril, Patriarch of Moscow, in the Church of Christ the Saviour in Moscow (2011), the service at the kelli of St Nicholas of the Dionysiou Monastery on its festival at Karyes on the Holy Mountain of Athos (2009), the all-night vigil at the Vatopaidi Monastery on the feast of the Vatopaidi Saints (2011), the vigil at the veneration at the Church of the Resurrection, Spata, at the reception of the sacred relic of the skull of St John Chrysostom (29 Jan. 2007), and the acts of worship during the visit of the sacred relics of St Seraphim of Sarov to the Church of St Tryphon, Pallini (4 - 5 Oct. 2008), presided over by His Beatitude Ieronymos II, Archbishop of Athens and All Greece, and a host of bishops of the Church of Greece. It has also recorded the following CDs: - 'St John Chrysostom, 1,600 years since his repose' - 'St Nicholas, Archbishop of Myra in Lycia' - 'The Athonite Theotokos', two CDs with hitherto unpublished chants by Athonite composers - 'Constantinopolitan Composers', two CDs with mostly hitherto unpublished chants by composers of the fourteenth to the early twentieth century - 'The Music of the Angels', with chants by Athonite and Constantinopolitan composers.