When it comes to discussing Dufay's broad and imposing output of songs, the most obvious point of reference is the complete recording by the Medieval Ensemble of London. In brief, this somewhat dated production is as impressive for its program as it is unimpressive for its individual performances. It is nonetheless central in a discography which is still relatively short on song recordings. The liner notes also provide a mostly excellent orientation to the specifics of Dufay's songs, in terms of dividing them into their relevant fixed forms, languages, and topics. In the past twenty years more details have come to light, helping to refine historical allusions and chronologies, but for the most part they would serve only to make the notes lengthier rather than adding any contradiction. The most tangible increase in knowledge is probably contained more in a broader historical perspective on Dufay's oeuvre than in anything else, and of course that affects how we eventually prioritize some of the specific facts regarding his songs. I do not want to dwell on a catalog here, of which there is also a nice chart in the New Grove, nor do I want to dwell further on individual recording selections, except to note again my personal recommendation list containing this repertory.
Whereas Machaut is known first as a great poet, the most important French poet of the mid-14th century, Dufay is known first as a composer. Many of the texts of his songs are known to have been supplied by others. However, despite a general inability to know for certain, some of the more personal lyrics almost must be by Dufay himself, and indeed the bulk of his chanson poetry is of indeterminate authorship. Nonetheless, the shift in emphasis between these two successive geniuses of French songwriting is a tangible one. Calling them successive, given the French orientation and sophistication of the Ars Subtilior is probably a stretch, but is a traditional view underscored by the relatively indistinct personal profiles of the otherwise fine composers of the intervening generations. Dufay's chansons share the sublimated, restrained quality of his age and so do not generally reflect the more public eroticism which developed in the madrigal a century later. However, at times they do become somewhat more overt, and it is an overall exuberance which marks them as such an important body of work. The poetry is conventional, but the musical settings are diverse and frequently striking. Dufay's leading contemporary, Binchois, remains more subtle and introverted, taking the sublimated style to an important height of expression. Binchois' superlative body of songs also helps to place this aspect of Dufay's oeuvre into some relief, making it the only genre in which a well-known & gifted direct contemporary also excelled.
The idea that Dufay took many of his stylistic cues from Dunstable and other English composers of that generation is evidently shortsighted when it comes to his songs. Dufay set primarily French verse, in the usual forms of the day. In England, few courtly songs survive from the era of Dufay, and even fewer from the era of Dunstable. England's legacy from the period is almost entirely liturgical. While it is certainly the case that Dufay's cyclic masses reflect many English traits, as do his hymns, and it has been tempting to prioritize these genres in his output due to our present taste for larger & sacred forms, viewing Dufay's songs as an artistic appendage to his liturgical output is simply untenable. In other words, Dufay's songs are not based on any English repertory, include some of the earliest and most striking masterpieces in his catalog, and cannot be separated dismissively from the stylistic genesis of his cyclic masses. Indeed the melodies and sophisticated phrasing in his later sacred output seem to be as motivated by chanson style as anything, and are fairly distinct from those of the more rough-hewn English works of Dunstable. This is another example of Dufay the synthesizer, and so it was fundamentally that the more "naïve" English harmonic styles could be charged with French rhetorical semantics which ensured their emerging dominance. This marks a contrast between Dunstable as Pythagorean mystic and Dufay as cosmopolitan lawyer, and without nuanced lexical implications there is no French style.
There are two main factors which make Dufay's songs so striking: They offer more straightforward and less syncopated melodies, and they are often aligned vertically in declamatory passages. The latter is the one aspect of Dufay's output which seems essentially unprecedented. Although late Ars Subtilior composers such as Matteo da Perugia, and even Johannes Ciconia, begin to offer "correlated" passages of this kind as a climax to syncopations, meaning that the vertical relationships themselves are not approached as structurally consonant, their music is not permeated with such structures as Dufay's sometimes is. To modern ears, his songs begin to sound modern, for precisely this reason. Songs were the musical backdrop to everyday life, and so rather than being placed in a position subordinate to his sacred works, especially given his excellence in the form, Dufay's songs must be placed first in his evolution. From where does this declamatory style come? Confidence in melody and rhetoric, perhaps. Only a handful of his songs are strongly declamatory, but when they are, they could be by no one but Dufay. Are these remnants of a classical Mediterranean style? The Italian of Quel fronte signorille in paradiso and his settings of the Constantinople lament (in Latin & French) suggest at least a motivation in this direction, something which recurs tangibly in French with Le Jeune more than a hundred years later and again in the mid-20th century.
To adequately render the rhetorical aspect of Dufay's songs takes detailed study combined with a special flair. Aside from the complete set, with its defects, there is not a single notable dedicated program, although there are quality tracks on several general programs. In this case, Binchois has actually fared better, not because his subtilitas is particularly easy to invoke, but because it does respond to interiorized ritual as the natural complement to in-depth study. Allowing the latter to elicit the exuberance of Dufay, especially as combined with rhetorical nuance, requires a personality aware of the intense study but less directly conditioned by it. It also requires a more restrained presentation style than the "tortured" utterances of Monteverdi, something we are beginning to see convincingly performed. Is there an implication here that Dufay's songs are the most difficult to perform well? Perhaps, somewhat, but it arises from a coincidence of role and personality, not the songs themselves. I expect they seemed outgoing & easy in their own era, when intense study would not have been needed or even desirable. Songs from this era continue to receive relatively too little attention, precisely because dealing with their intricate allusions & rhetoric is frequently more daunting in its variety than adopting the uniform mysticism of sacred works. However, ultimately both must be understood in order to form a proper basis for interpreting music of this era, especially in the case of Dufay.