(Re: the Text, p. 47 & p. 151)
String Crossing refers to the technique of shifting the right-hand up and down across the strings. Although this is a vital element of right-hand technique, requiring a high level of skill, to my knowledge an effective procedure for developing this skill has not been established. Thus, no common reliable knowledge of this problem exists among teachers and performers. That it is a challenging technique should be self-evident. Correctly approached, using the prepared-stroke, the habit of moving a finger to sound its string in the most effective natural manner (involving optimal leverage) can be readily acquired.
If this technique is to be consistently applied in sounding strings, precise placement of the hand must also be consistent; if not, the finger movement must be changed to accommodate each new situation. The habits essential for skillfully sounding strings obviously do not develop well in an environment of constant adjustment and change. Yet the misguided student must deal with just such conditions (of constant change) while seeking to develop habits of accuracy in sounding strings. Thus the position of the arm and hand in relation to the strings is crucial. Among the few teachers who recognize the problem of crossing there appears to be a lack of agreement even on the matter of basic arm movement.
While some guitarists advocate moving primarily at the elbow, certain others recommend moving mainly at the shoulder joint and, still others advise moving at both the elbow and shoulder joints together. Occasionally someone will suggest deviating the wrist or rotating the forearm along with any combination of the above. Although a proficient guitarist, depending on the background of training, must be able to move the arm in whatever manner the given musical situation demands, it’s only reasonable to have a secure basic approach which one generally uses from which to depart when there is a practical need.
In developing the most effective string crossing technique, it is just as important to be aware of what not to do as of what to do. The first five of the following six possible options explain what to avoid while number six, as indicated, is the most effective approach:
1) Moving solely at the shoulder Joint
Despite being advocated by at least one well-known “school,” it’s simply not practical as a basic technique and is, therefore, an extremely misguided approach.
2) Simultaneously moving at both the elbow and the shoulder joints
This is a complex movement and consequently should be done only for special tonal effects as in playing sul ponticello (It., pron., sool-pohnti-chello), abbreviated pont, which means to play near the bridge, or in playing sul tasto (It., pron., sool-tahs-toh), or simply tasto, which means to play near or over the end of the fingerboard.
3) Crossing by deviating the wrist sidewise
This is contrary to the principles of leverage and is therefore not practical.
4) Crossing by keeping the arm rigid and reaching with the fingers
This is extremely inefficient, thus placing the fingers in highly awkward positions and removing all consideration of optimal leverage.
5) Holding the arm more or less rigid and rotating the forearm
This negatively affects the tilt of the hand and so tone production.
6) Moving mainly at the elbow—✓
For the reason that primarily only one joint is involved, is the least complex and therefore the easiest and most accurate manner of shifting the hand down and up across the strings. The occasional assertion that crossing the strings at a slight angle, as occurs when moving solely at the elbow, produces an objectionable change in timbre and clarity of tone is not valid but rather is a matter of proper finger placement and movement of the tip and nail—of not dragging the nail, even slightly, across the winding of the bass strings—but instead as directly across the string as possible.
Fluency in String Crossing requires considerable practice and is acquired in conjunction with later training of p and the fingers. (See the Text under Right-Hand String Crossing, pp. 47 & 151, and watch video 34—String cossing.).