The page of music you have with this worksheet is the bass part
to the 2nd movement of Autumn. The music was not just intended
to be played on bass instruments like the cello or double bass.
In 1730, when this music was first published, it was usual too
that chord playing instruments (like the organ, harpsichord, lute
or theorbo) would play the bass line of the music. Whichever instruments
were chosen to play, they were usually grouped together under
the heading, the basso continuo group.
To show the chord-playing basso continuo instruments what
to play, the composer used a system of figures (numbers) written
above the bass notes to show how the chord should be built up
from the given bass note.
Look at the music on the page called Autumn 2nd Movement: Figured
Bass
In bars 1-4 of the music the bass note is always D.
In bar 1 the 3 & 5 above the note mean that F & A must
be played with the D ( i.e. D-F-A or a D minor chord in root position)
In bar 2 the 3 & 6 above the note mean that f and Bb must
be played with the D (i.e. D-F-Bb or a Bb major chord in first
inversion)
In bar 3 the 4 & 6 above the note mean that G and Bb must
be played in the D (i.e. D-G-Bb or a G minor chord in second inversion)
And so on.......
Note the following points carefully:
1. The bass note is always counted as note number 1 when working
out the figures.
2. When the bass note changes ( as the C# in bar 5), then you
must work out the figures from the new bass note (here, C#)
3. The key signature here will always change Bs into Bbs.
4. When you see a #-sign or a +-sign by a number, a slash through
a number or a natural sign this means that the note indicated
must be raised by a semitone.
5. When you see a flat-sign by a number this means the note indicated
must be lowered by a semitone.
Your exercise:
is to learn to play the chords fluenty and steadily, keeping to
the slow 3/4 time.
You can play all the notes of the chords together if you wish
or you can spread the notes out. You might even try to make little
rhythmic patterns out of the notes. Realising a figured
bass (as it is called) is a form of improvisation, so you have
quite a lot of freedom.
On the MIDIfile you can hear these three different models of playing
the figures.
When you play along with the strings on the MIDIfile using
an electronic keyboard, set it on a harpsichord, guitar or organ
sound. You may try recording your improvisation to an unused track
on the music sequencing programme playing the MIDIfile.
The numbers in brackets are not usually given. Look carefully
and you will see that they are most frequently the numbers 3 &
5. Because this is the simplest way of building a chord, the combination
1-3-5 was often left out by the composer. If the performer was
unsure of the chord, this would be the first combination to try
out.