A brief digression forward in time: The figure of Orpheus, concerned as it is with the power of music and poetry, acquired a large and quasi-mystical stature in the Renaissance. The musical efforts of Ficino, the elder Galilei, Monteverdi, and others were only one facet of a broad and deep-rooted preoccupation with the arch-poet. One way to approach this is through getting acquainted with the idea of the prisca theologia, the idea that "a single, true, theology exists, which threads through all religions, and which was given by God to man in antiquity."
A seminal scholarly article about the prisca theologia and the figure of Orpheus that explores some Renaissance thinking on this subject: is Orpheus the Theologian and Renaissance Platonists by D.P. Walker. (We last brushed shoulders with the Cambridge Platonists while reading Milton.) If you're interested in having a look at Walker's article, let me know.
The influence of the figure continues into the modern era, as Jutta noted with Rilke, whose Sonnets to Orpheus are a sustained meditation on poetry, music, and voice. (Translation by Robert Hunter here.)
A poet writing in English who seems fully immersed in Orphic lore would be Yeats. This article takes a look at his esoteric involvement with, among other things, magic.