Tallis made two five-part settings of the hymn Te lucis ante terminum, one based on the plainchant melody to which this hymn was sung on Sundays and simple feasts when the choir was ruled, and the other based on the melody sung on ordinary weekdays and feasts without rulers. In each case he provided polyphony only for the second of the three verses, and placed the chant melody unadorned in the highest voice. The festal setting is slightly the more elaborate of the two, the vocal lines being rhythmically more independent of each other, and each phrase of the melody being anticipated in one of the alto lines before entering in the treble, whereas the ferial setting eschews such anticipation. It is rather surprising that Tallis set these verses in compound duple metre, for although this metre had been common in English music during the early fifteenth century it had subsequently fallen out of fashion and been in desuetude for more than a hundred years; Tallis may possibly have chosen it in order to reproduce the effect of an oral tradition of singing plainchant hymns metrically.
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