Something like the Bach or Brahms motets presuppose a certain technical foundation, available mainly in this earlier work. Intonation problems give them a muddier tone, with the basses tending to hit under pitch. By the middle of the piece, I found myself in the middle of a vibrant performance. The choir continues at peak form in the Dufay. In fact, my only quibble concerns the underpowered tenors, who nevertheless do well with what they have.
Attacks are clean, and rhythms sharp.
The assignment of the incipits to a particular tenor at first startled me, since this guy's tone is more nasal than a krummhorn. Still, it doesn't detract significantly from the performance, and I got used to it. Ross certainly knows how to shape these pieces, while conveying their architecture. So often performers, even the historically-correct ones, press this music out as an undifferentiated wad. Monteverdi were all a part - treated religious music as drama.