One of Byrd’s systematically canonic work for keyboard is the Lesson of voluntarie, two parts in one in the 4th above
(BK26); it uses essentially the same canonic technique (since the interval of a ‘4th above’ is structurally the same as the ‘5th below’ used here). That work was through-composed, being a voluntary, or fantasia. The canon is present in strict form in the three principal phrases; in each of these, following the soprano entry, the alto part enters a fifth lower, after four minim beats. In the three varied repeats, the canon’s shadow continues to control all the imitations, but Byrd freely allows it to be hidden at the beginning and end of phrases by ornamental figuration in the top part.
The third strain starts on the chord of F major, emphasizing the Mixolydian mode. For some reason there appears to be no galliard associated with this or the next work. Being a ‘16-bar’ pavan, running to 96 semibreves, Byrd cannot have intended any association with the unattached galliard in the same Mixolydian G major (BK77). In any case, the absence of a galliard in the authoritative Nevell source would virtually forbid our linking one with it. This pavan is one of Byrd’s most concentrated and demanding works, with a particularly rich harmonic language and an unusually plangent treatment of dissonance.
from notes by Davitt Moroney © 1999