Comparison Casio Casiotone CT-S1-76 vs Casio Casiotone CT-S1

The number of keys provided on the digital piano keyboard.

The immediate range of the instrument depends on the number of keys — that is, the set of notes that can be played on it without resorting to octave transfer or transposition (see below). Most digital pianos have 88 keys, the same number as a regular piano; thus, the ranges in electronic instruments most often match those of real pianos. However, smaller models are also produced — usually 61 or 73 keys (as in most synthesizers). This number of keys is found in two types of digital pianos — in inexpensive entry-level models and in some professional instruments designed mainly for "genre" music (rock, gospel, etc.), and not for classical piano parts.