The Technique of “Isolating” Variables
October 31, 2018
Whenever a passage involves an intricate balance between two concerns, such as rhythm and pitch, pitch and fingering, etc., there is a method by which one of the two can be “held constant” while allowing only the other one to change.*
In the following examples we separate apart two intertwined issues, putting emphasis first on one and then the other, by holding the other one constant. Each is mastered singly before putting them back together again.
If rhythm and pitch are changing at the same time:
Make all the pitches just one and the same pitch, and play that note in the rhythm of the passage.
Play the sequence of pitches as written but do so in a “neutral” rhythm, (for instance giving each note the same duration).
If loudness and pitch are changing at the same time:
hold the loudness constant and let only the pitch vary.
hold all the pitches to one repeating note, and only let the loudness vary.
If an intricate series of notes also requires a difficult pattern of fingering:
Play every note with one and the same finger.
Stay on one note, but use the fingers in the order that they will need to be used when playing the passage in its normal form.
‘bunch’ up the finger tips and use them as a single unit on just one note and play the rhythm of the passage.
If the two hands are doing things that are quite different from one another and, thus, hand coordination becomes an issue:
Have both hands play the right hand’s notes, but in two different octaves. Then reverse the procedure, and have both hands lay the left hand’s notes in two different octaves.
If a melodic line involves sudden changes of register (octave).
Put all the notes of the melody into one and the same octave (a perfect example is Brahms: Op 117 No. 3, the middle section).
If it is difficult to play a melody in octaves in one hand. Use the pinkie to play just the pinkie notes. Then use the thumb to play just the lower notes.
If there is a variety of articulation marks within a small group of notes.
Play it all very legato; then all very staccato; then all accented; then all sotto voce.
Then add back the articulation. By this time you will be practiced in executing each type of articulation.
If it is difficult to play something slowly (or rapidly) enough:
Play it first at the opposite extreme of tempo. This procedure is especially useful for learning to sustain a long phrase or melody, that evolves over many measures. First play it extremely rapidly.
You will get a sense of the main outlines and directions in the phrase. Then slow it back down, and you will notice that the way the notes adhered to each other in the fast tempo is preserved into the slower tempo.
Mention is also made of these types of procedures in the blog:
* In mathematics, when there are several different ‘variables’, all intermixing and interacting with each other in a single equation, mathematicians, in order to gain understanding of how the equation behaves as a whole, use a procedure in which they treat all of the variables except one as if they were no longer capable of varying but were held constant. Then, one can go through each of the original variables in turn, each time making it, for the nonce, the only one varying. This is called partial differentiation.