Comparison Kurzweil KA70 vs Casio Compact CDP-S100

Type of action used in digital piano keys.

— Hammer. A mechanic that mimics the feel of playing a real piano as closely as possible. Hammer action keyboards not only provide velocity and force-dependent sound dynamics, they also provide a distinctive response with each press. These mechanics are complex and expensive, but they are considered the most advanced and suitable for digital pianos, and therefore are used in most models.

— Active. In the case of digital pianos, the active keyboard can be described as a simplified version of the hammer action described above. The sound produced when pressing such keys also depends on the force and speed of pressing, however, the keys themselves have less rigidity and do not give the full feel of a piano keyboard. On the other hand, such mechanics are cheaper. As a result, it is found mainly in low-cost models, as well as some professional instruments, positioned more like electric organs.

The third type of mechanics — passive — assumes that each time you press a key, the volume will be the same, regardless of the strength and speed of pressing. Such keyboards are not used in digital pianos — they are too primitive and not very functional for this class of instruments; however, models with adjustable sensitivity may provide switching the keyboard to a "passive" format (see below for more details).

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").

Auto accompaniment feature on the digital piano.

Auto Accompaniment is a melody of a specific style played by the instrument under user control. Such control is carried out by the left hand: the musician takes certain chords on the left side of the keyboard, and the electronics of the instrument adjusts the auto accompaniment melody to the key of the taken chord. Thus, this function allows you to accompany the main part with a full-fledged accompaniment, while the musician only needs to set the chords.

Among digital pianos, unlike synthesizers, this function is rare. This is due to the general specialization of this class of instruments (not least professional music-making, including as part of an ensemble or orchestra). However, auto accompaniment is available on both relatively simple and high-end digital pianos.

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 range over which the tempo of the sound played by the instrument can change. It can be either a built-in melody or a part recorded on a sequencer, or an auto accompaniment, a tutorial or a metronome. For more information on all of these features, see the corresponding glossary entries. Here we note that a change in tempo is often required in fact — for example, to speed up an initially "sluggish" accompaniment or slow down a training programme that is difficult to master at the original tempo.

Tempo is traditionally indicated in beats per minute. The classical, "academic" range covers options from 40 bpm ("grave", "very slow") to 208 bpm ("prestissimo", "very fast"), however, in modern digital pianos, the working range of tempos is often significantly wider.

The presence of a sequencer in the design of a digital piano.

This function allows you not only to play music on the instrument, but also to record it with the possibility of later playback. However, this is at least; in addition to recording the parts of the instrument itself, the sequencer can provide recording an audio or MIDI signal from the corresponding input, mixing several parts (including recording the music being played over the music being played “on the go”), working with the parameters of individual tracks (volume, tone, timbre), as well as specific functions such as quantization (smoothing uneven tempo). The specific functionality of the sequencer may be different, it's ok to check it before buying. However, anyway, this function can be a good help for the musician; it is especially useful for those who are not limited to the performance of ready-made music and want to compose their own compositions.

Possibility of dividing the keyboard into two parts so that the parts of the left and right hands are played in different timbres. This allows you to simultaneously play two disparate parts on the instrument — for example, accompany a piano melody with chords from a string orchestra or organ sounds. Specific combinations of timbres are most often pre-recorded in memory, however, there are models in which the musician himself can choose timbres for each part of the keyboard.

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.