Comparison Kurzweil KA90 vs Kawai ES100

The number of voices supported by the digital piano — more precisely, the maximum number of voices that the instrument can play at the same time.

This parameter should not be confused with the number of notes that can be played simultaneously on the keyboard. The fact is that in many timbres, several voices (tone generators) are used for each note at once — this is the only way to achieve a more or less reliable sound. Thus, the required number of voices can be many times higher than the number of notes — for example, the simplest chord of 3 notes may require 9 or even 12 voices. In addition, tone generators are used to play auto accompaniment parts and built-in songs (see below), and here the number of voices can already be measured in tens.

In light of all this, polyphony of less than 90 voices is typical mainly for relatively simple and inexpensive instruments that are not designed for complex tasks. The smallest number found in modern digital pianos is 32 voices. It is desirable for a more or less solid instrument to have at least 96 voices, and in top models this figure can reach 256.

The number of built-in sounds provided by the Digital Piano.

Despite the name, digital pianos are extremely rarely designed to imitate the sound of only a piano — the electronic hardware allows them to provide other timbres of sound. In addition, even the piano has its own varieties — for example, among the grand pianos there are 6 main classes, from large concert to miniature. So the built-in sounds can cover different kinds of pianos, as well as other instruments and sound effects.

The abundance and variety of timbres in digital pianos as a whole is not as great as in synthesizers, however, in this category there are very “charged” models, with a hundred timbres or more (in the most multifunctional, this number can exceed 900). However, it is worth specifically looking for a “multi-instrumental” model if you do not intend to be limited to the sound of the piano and would like to have more freedom of choice. It is worth remembering that a specific set of timbres can be different.

If the instrument is bought exclusively as a piano, then here, on the contrary, it is worth paying attention primarily to solutions with a small number of timbres. Such models are not only cheaper than "universals" — they can also sound better (due to the fact that there are few timbres and the manufacturer can carefully approach the sound quality of each built-in "instrument").

The number of Auto Accompaniment Styles (see above) originally stored in Digital Piano memory.

Different auto accompaniment styles differ from each other in the same way that different melodies differ from each other — in tempo, time signature, rhythmic pattern, set of instruments used, etc. Accordingly, the more styles initially available in the instrument, the wider the choice of the musician and the higher the probability of finding the option that best suits a particular situation. However even numerous styles does not guarantee that among them there will be a suitable one; in addition, we note that with the same number of styles, their specific set in different instruments can also be different. However, custom styles can be provided for this case (see below).

Summarizing, we can say this: if you plan to work intensively with auto accompaniment, in addition to the number of styles, it will not hurt to clarify their specific range.

The presence of a training mode in the digital piano.

As the name suggests, this mode is designed to teach the game. At the same time, usually, it provides different levels of difficulty — from the most basic, for those who are just starting to master the "keys", to the advanced one, which allows you to train your technique and improve your existing performance skills. However, anyway, the principle of learning is the same: the tool independently tells the student which keys to press at one time or another. Such hints can be in the form of a backlight (see above) or as a graphic on the display. Such a method is doubtful from the point of view of classical academic learning, however, it is undoubtedly more convenient and faster than reading musical notation. Moreover, the instrument can also play the role of an examiner — launch prompts at the original tempo of the melody and check how accurately the student hits the notes.

Also note that the learning mode requires the obligatory presence of a metronome (see below).

The presence of an octave shift function in the digital piano.

This function makes it possible to "shift" the sound by a certain number of octaves up or down — for example, in such a way that the bass register sounds on the keys of the first octave, or vice versa, the first octave "slid" lower, into the bass, and notes of the second sounded in its place or even the third octave.

This feature significantly expands the range of the instrument, allowing you to play notes that were not originally covered by the keyboard. This is especially important for instruments with 61 or 73 keys (see "Number of Keys"), but octave shifting is not uncommon in full-sized 88-key models — it can be useful when splitting the keyboard (see above), when available for each hand the range is noticeably reduced, and the batch can be very low or very high. However, there are other options for using transfer — for example, so that when playing an updated version of the melody, you do not have to move from the usual octaves.

The presence of the chorus effect in the digital piano.

Initially, this effect was developed as an attempt to simulate the choral sound of several instruments of the same type. Even a perfect choir never plays 100% in sync, which is what the creators of the chorus tried to reproduce. This effect works as follows: several copies are taken from the main signal, which are played along with it — but not strictly simultaneously, but with a small (up to 30 ms) delay, selected randomly for each individual signal. This really allows to imitate the effect of polyphony to a certain extent, however, such sound is still far from a full-fledged choir. However, the chorus itself is quite interesting as an additional effect.

The ability to change the brightness of the sound of certain timbres or tracks.

Brightness determines the overall colour of the sound — from soft, smoothed to sonorous, sharp. This feature allows the player to adjust this coloration to their preference, and thus further expands the possibilities for customizing the sound of the instrument.

The presence of a pitch controller(Pitch Bend) in the design of a digital piano.

Such a controller allows you to smoothly change the pitch of the note being played within a small range (usually up to a semitone up or down). In this case, control is carried out using a wheel, a lever, or another similar element that allows the musician to manually adjust the speed and limits of frequency change (including creating the effect of a note “trembling” in frequency). This function allows you to simulate the playing techniques of some instruments (for example, tightening the strings on a guitar) and gives an unusual sound to timbres that were not originally intended to have such effects.

Additional features and sound customization options provided by the instrument in addition to those listed above. In this paragraph, usually, various original proprietary technologies and solutions are indicated; the specific meaning of these functions is best specified in the documentation for the tool.