Finger crossing

What it means

In piano technique, Übersetzen (finger crossing) designates a finger reaching over the thumb, to continue a scale or a run without interruption. Its counterpart is the thumb-under (Untersatz), in which the thumb is led beneath the hand to a new position.

The two movements belong together and form the basic framework of scale and run playing. In upward playing with the right hand, the thumb passes under; in downward playing, the third or fourth finger crosses over the thumb. In the left hand the directions are reversed.

The term is not used uniformly in method books: some designate both movements together as “Übersetzen”, others only the crossing-over. Often the word is used imprecisely for the thumb-under; in the strict sense, however, it means the opposite movement.

In the notation

Finger crossing and thumb-under are not notated specially but result from the fingering, which stands as a numeral above or below the notes. A change from a higher numeral to 1 indicates a thumb-under, a change from 1 to a higher numeral a finger crossing.

Musical use

The technique makes it possible to play runs bound beyond the span of a single hand position. It was systematically developed in the eighteenth century; older fingerings partly did without the thumb and worked with adjacent fingers striking one over the other. The modern technique with the thumb-under becomes established with the keyboard music of the Viennese Classical era.

With finger crossing, a finger reaches over the thumb; with the thumb-under, the thumb passes under the hand. Both techniques are needed to play scales and runs without interruption.

Performance practice

Keep the hand calm and let the thumb travel early, already while the other fingers are playing. Take care that the change does not become audible — no accent, no gap. Practise scales slowly with deliberate thumb movement before you increase the tempo. And keep the wrist loose; tension makes the transition uneven.