A descant is a higher melody sung above a song's tune, usually by some or all of the choir's sopranos or trebles, while everyone else sings the tune or the harmony beneath. In hymns and carols it most often comes on the last verse or the one before, to lift the ending.
Where you'll hear one
The most familiar descants are on Christmas carols, soaring over one of the last verses at carol services and concerts. Many hymns have them too, written for special occasions or for a choir to add above a congregation singing the tune.
What makes a descant
A descant is a countermelody: a tune of its own that fits with the main one.
- It sits above the tune, so it can be heard without drowning it.
- It moves when the tune holds, and holds when the tune moves. That way the two lines take turns being heard instead of competing.
- It fits the same chords, so it adds to the harmony rather than fighting it.
- It's decoration. The tune is still the song, so sing the descant lightly enough that the tune comes through.
Where the word comes from
The word comes from the medieval Latin discantus. In the Middle Ages, discant meant a way of adding a voice above a chant melody, moving mostly note against note. Today it means the high line over a tune.
A descant recorder is something else: it's the usual school recorder. "Descant" is its British name; in North America and elsewhere it's the soprano recorder.
How to sing a descant
Five steps, from the tune you already know to a line of your own over it.
O Come, All Ye FaithfulGetting the voices ready...
All of O Come, All Ye Faithful, from "O come, all ye faithful, joyful and triumphant, O come ye, O come ye to Bethlehem;", in its parts: the tune with the others under it. Your part is the Soprano. Press a voice to take it out of the harmony or bring it back.
Know the tune first
You'll sing against it the whole time, so know it well enough to hear it under you without following it.
Learn the descant on its own
Sing it slowly until you can hold it with no help, then at the song's speed.
Find your first note
A descant often starts somewhere unexpected, high above the tune. Check your first note before you start, with an instrument or the free pitch pipe.
Sing it lightly
Keep the top notes light and easy, in your head voice, rather than pushing for volume. A descant should float over the choir, not shout above it.
Hold your own line
The tune will pull at you, especially where the two lines cross or meet. Practise with the tune playing, and listen for both lines at once.
Practise with Stackapella
Stackapella's arrangements don't include descants. But holding your own line while the tune pulls at you is the same skill every harmony part needs. O Come, All Ye Faithful, whose best-known descant soars over its "Sing, choirs of angels" verse, has an alto part that mostly moves a third or a sixth beneath the tune and climbs above it on the last note of "Bethlehem", as a descant would. Learn it on its own, then sing it with the others and keep your line where the two part ways. Every one of the hymns has the tune in the soprano and three parts to hold against it, for the same practice.