This three disc boxed set is a reissue of three previous individual recordings by Ensemble Binchois of Guillaume de Machaut's compositions.
The first disc is of the Messe de Notre Dame, one of the treasures of world music. This is the most stunning, enrapturing rendition I have heard so far (and I think I have eight different recordings of the mass at the last count) - the countertenor line in the polyphonic Ordinaries is sung by the great Andreas Scholl, whose presence lifts this into the transcendental.
The second and third discs contain selections of Machaut's secular chansons interspersed with pieces of spoken poetry - Machaut was an accomplished poet as well as a composer, and he heavily influenced his contemporary Chaucer. Unless you can speak medieval French you will probably not gain a lot from these poems to be honest. Mind you, at this bargain price it's worth it just for the mass on the first disc alone.
Three discs in double jewel case with a brief booklet; there is a fourth CD-ROM containing the Latin/old French sung texts for all the pieces with English, German, French & Spanish translations, as separate PDF documents.