This lesson refers to the keyboard reconstruction question (Q2. ABRSM Grade 8 Music Theory).
Texture and Part-Writing
The number of notes played by each hand can vary considerably within the same piece.
When more than one note is played, the texture could be either polyphonic (two or more independent voices) or homophonic (chordal accompaniment). Make sure that the texture is consistent and does not flit about from one type to the other for no reason.
Here are some examples of different textures.
This Schumann piece entitled “Armes Waisenkind” (“The Poor Orphan”) begins with a homophonic texture. A chord is played on each quaver (eighth note) beat, and the melody is in the soprano/right hand. Generally, two notes are played in each hand, but in bar 1, the G#/B is followed by a single A. Can you think of a reason why?
The answer is, that since G# is the leading note, it most logically leads to A. If Schumann had continued in 3rds, the harmony would be wrong (A-F would not fit the A minor harmony), and falling to E would produce a thicker-sounding chord.
This extract from the Rondo movement of Dussek’s 5th Sonatina for piano (Op.20) has a more polyphonic texture. The right and left hands have clear, independent melodies.
This “Old French Song”, transcribed by Tchaikovsky, uses a tonic pedal G in the bass, and the left hand also has its own melodic line to help thicken out the texture of the piece.
Notice what happens in the notation when the pedal and melodic lines coincide (boxed), the G is written with both an upwards and downwards stem, to indicate that it belongs to both parts.
Look for clues about what is expected in terms of texture. For example, if you are given a bar which seems complete, but the stems are apparently pointing in the “wrong” direction, this is a clue that you need to write a rhythmically different second part on the same stave, with stems pointing in the other direction. (If the rhythm is not different, there is no reason to notate it as separate parts).
In this example, which bars need another part adding to them?
In the right hand, bars 1-3 all contain notes above the middle line, with stems pointing upwards. This indicates that a rhythmically different lower part, with stems down, should be added.
In the left hand, bar 3 needs another part adding above the Cs. Here is a possible rendering:
Where there are two parts on one stave, the bars should be complete for both parts. If one part ends before the end of the bar, complete it with the necessary rests. Rests can be positioned higher or lower on the stave, to make it clear which part they belong to.
Here, the rests in the centre of the stave complete the first beat of each bar in the right hand. In the second beat, additional quaver (eighth) rests are needed, placed lower down on the stave to show they belong to the lower part.