The Shape of Keys
2.1 The keyboard of the piano accordion offers the way of development. With the lack of pedal on accordion, legato "seams" always need an audio control. That is why accordionist have developed a distinct technique of sound making, which is based on sliding the fingers over the white keys of diatonic scale. It is particularly noticeable when linking the voices of multi-voice structure (chords, polyphony, etc.) in keys with small number of sharps and flats. Starting with key-signature with three sharps or flats or more this kind of technique becomes ineffective due to the neighboring surfaces of black and white keys been on different levels, which makes sliding practically unusable. That is why, all the keys in Kravtsov’s keyboard have the same elevation.
2.2 If we correct the shape of keys, this problem would be solved.
2.3 The distance between points 'A' and 'B' we can enlarge, if we locate them differently - as 'A1' and 'B1'. Linking them with a direct line, we get an enlarged length of neighboring surfaces that gives us necessary. By changing all the other adjoining edges of neighboring keys in a similar way, we obtain the shape of keys that is optimal for performing.
That way, after making necessary changes on the other contact surfaces of keys, we got the optimal shape of keys for sound making. At the same time, it allows to use all techniques, fingerings, and hand positions have been developed by the accordionist before.