[1.II.11] Parallel Sets
Now that the LH CEG chord is satisfactory, try to switch suddenly from the chord to the quadruplet at several different bounce frequencies. You will now have to move the fingers but keep the finger motions to a minimum. To successfully switch, you will need to incorporate the proper hand/arm motions (see Fink, Sandor) discussed later but, that's advanced stuff, so let's back-track a little. Let's assume that you cannot switch, so that we can demonstrate a powerful method for solving this very common type of problem.
The most basic way to learn how to play a difficult passage is to build it up two notes at a time, using the chord attack. In our (LH) CGEG example, we start with the first two notes. A two-note chord attack (strictly speaking, an interval attack)! Play these two notes as a perfect interval, bouncing your hand and fingers (5 and 1) together up and down as you did previously with the CEG chord. In order to play these two notes rapidly one after the other, lower both fingers together, but keep the 1 finger slightly above the 5 so that the 5 lands first. It is just a rapid two-note rolling interval. Since you are bringing both fingers down at once and only delaying one slightly, you can play them as closely as you wish by decreasing the delay. This is how you slow down from infinite speed!
Is it possible to play any combination of notes infinitely fast in this way? Of course not. How do we know which ones can be played infinitely fast and which ones can't? In order to answer this question, we need to introduce the concept of parallel play. The above method of lowering fingers together is called parallel play because the fingers are lowered together, i.e., in parallel. A parallel set is a group of notes that can be played simultaneously with one hand. All parallel sets can be played infinitely fast. The delay between successive fingers is called the phase angle. In a chord, the phase angle is zero for all the fingers. These and related concepts are explained more systematically in section IV.2. The "parallel set" terminology is also needed to avoid the confusion arising from the fact that in music theory, "chord" and "interval" have specific meanings that are not applicable to parallel sets. The highest parallel set speed is attained by reducing the phase to the smallest controllable value. This smallest value is approximately equal to the error in your chord playing. In other words, the more accurate your chords, the faster will be your maximum attainable speed. This is why so much space was devoted above to practicing perfect chords.
Once you have conquered the CG, you can proceed with the next GE (13), then EG and finally the GC to complete the quadruplet and conjunction. Then connect them in pairs, CGE, etc., to complete the quadruplet. Note that CGE (513) is also a parallel set. Therefore the quadruplet plus conjunction can be constructed from two parallel sets, (513) and (315). In this scheme, 3 is the conjunction. This is faster than the use of 2-note parallel sets, but more difficult. The general rule for the use of parallel sets is: construct the practice segment by using the largest parallel sets possible that are consistent with the fingering. Break it up into smaller parallel sets only if the large parallel set is too difficult. Section III.7 discusses details of how to use parallel sets.
After you can play one quadruplet well, practice playing two in succession, then three, etc. Eventually, you will be able to play as many as you want indefinitely! When you initially bounced the chord, the hand moved up and down. But in the end, when playing the quadruplets in rapid succession, the hand is fairly stationary; you will also have to add hand motions, etc., -- more on these topics later.
The second difficult section in Fur Elise ends with an arpeggio containing three parallel sets: 123, 135, and 432. First practice each parallel set individually (e.g. 123), then add the conjunction (1231), then connect them in pairs, (123135) etc., to build up the arpeggio.
In order for any practice segment to sound smooth and musical, we need to accomplish two things: (1) control the phase angles accurately (finger independence) and (2) connect the parallel sets smoothly. Most of the finger/hand/arm motions described in the references are aimed at accomplishing these two tasks in ingenious ways. We will discuss many of those topics in Section III. The references are useful companions to this book. In order to help you decide which reference to use, I have provided (brief) reviews for several of them in the Reference section.
You will need to read most of section III in order to know how to use parallel sets most effectively. The parallel play described above is called "phase locked" parallel play and is the easiest way to start, but that is not your ultimate goal. In order to acquire technique, you need complete finger independence, not phase locked fingers. Parallel sets accomplish two things: teach your brain the concept of extremely fast play, and give your hands an idea of what rapid play feels like. For those who have not played that fast, these are totally new and foreign experiences. Parallel play gets you up to speed, so that you can experiment with different motions to see which ones work. Because the methods described here allow you to try hundreds of trials in minutes, this experimentation can be conducted quickly.