Natural key

What it means

Natural keys (German Untertasten) are the broad, lower-lying keys of the keyboard that correspond to the natural notes C, D, E, F, G, A, and B. Opposite them stand the narrower, raised sharp/flat keys for the chromatic notes. The designation by position is more precise than the one by colour, for the colour is not fixed: historical instruments, for instance many harpsichords and fortepianos, have dark natural keys and light sharp keys — exactly the reverse of today's piano.

Musical use

The arrangement of seven natural keys and five raised keys per octave maps the diatonic scale and is at the same time the hand's aid to orientation: from the groups of two and three raised keys, every position can be felt out. For playing technique it follows that keys are differently comfortable to finger; C major lies on the natural keys, while pieces rich in accidentals demand constant switching between the levels. Some composers use this peculiarity deliberately and write figures that live off the comfortable fingering of a particular group of keys.

Performance practice

On the natural keys, do not play too far forward, but where the hand reaches the raised keys too without shifting; the right depth of the hand within the key field saves many movements. Keep the fingers arched, so that no pulling movement of the arm becomes necessary when changing between the levels. Practise scales in all keys, to make the different fingering comfort familiar. Clean the key surfaces with a slightly damp cloth and without harsh agents. With historical instruments, a brief look at the colouring is worthwhile, so that orientation is not misleading.

Bear in mind that key width and key depth on historical instruments deviate from today's measurements: fingerings that are uncomfortable on the modern grand can fall easily there, and vice versa. Check this before you transfer fingerings. Watch the depth at which the hand works within the key field, because it decides how far the reaches to the raised keys are. Clean the surfaces without harsh agents and avoid moisture at the key edges, since the covering and the wood beneath suffer from it.