{"product_id":"guy-of-saint-denis-tractatus-de-tonis-1","title":"Guy of Saint-Denis, Tractatus de tonis","description":"The Tractatus de tonis of Guy of Saint-Denis (written ca. 1300-10) differs from other treatises on plainchant in the depth of its analysis of the various tones into which chant was traditionally classified. Guy's treatise presents itself as a synthetic overview of both the theory and practice of plainchant in a way that combines the practical reflection of Guido of Arezzo with ideas of more Aristoteleian inspired theorists such as Johannes de Grocheio and Peter of Auvergne.","brand":"Medieval Institute Publications","offers":[{"title":"Default Title","offer_id":54226553602392,"sku":"9781580442992","price":43.99,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0278\/1295\/4195\/files\/9781580442992_51e85529-4d06-4038-a57f-b959fe81cb6a.jpg?v=1754593227","url":"https:\/\/agendabookshop.com\/products\/guy-of-saint-denis-tractatus-de-tonis-1","provider":"Agenda Bookshop","version":"1.0","type":"link"}