Comparison Roland RP-102 vs Kawai KDP90

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 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 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 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.

— Mini-jack (linear). Any line input is designed to receive an audio signal in analogue format. Such an audio signal can be played back by the instrument itself through the built-in speakers, external speakers or headphones, switched to external equipment (for example, an amplifier or audio receiver), or recorded (if you have a sequencer, see above). In digital pianos, the most popular is the first option — playback; typically, the line-in sound either serves as an accompaniment to the main part or provides additional effects. As for the mini-Jack standard, this is a miniature plug, also called "3.5 mm" and known to many as a standard audio jack on a smartphone, laptop or computer. However, this standard is also very popular in digital pianos — among external signal sources, mini-Jack plugs are generally more common than full-size Jacks.

— Jack (linear). Line input using a Jack type connector (aka "6.35 mm"). In terms of purpose, such an input does not differ from the mini-Jack type input described above. As for the connector, it is almost 2 times larger than the mini-Jack in diameter — however, given the dimensions of digital pianos, this cannot be called a serious drawback. At the same time, the Jack socket provides a better and more reliable connection, with less likelihood of interference. At the same time, for a number of reasons, this type of connector is used somewhat less frequently in digital pianos.

— MIDI in. An...input that allows the Digital Piano to receive MIDI signals from external equipment. MIDI is a standard signal format in electronic musical instruments; such a signal (MIDI-event) is created for each keystroke and contains information about the note number, strength, speed and duration of pressing; these signals can then be recorded and/or played back in a specific tone. The ability to receive MIDI events from external devices can be useful, for example, when playing two keyboard instruments at once (to play all the music on one of them, with better sound quality), or to use the digital piano as an adapter for another instrument that does not having the desired tones. In addition, technically, a MIDI signal can be switched to other devices (see "Outputs — MIDI thru").

— USB to device (type A). USB connector that allows you to connect various external devices to the digital piano. However, most often the range of such devices is limited to "flash drives" and other drives. However, even this functionality can provide very extensive additional features: you can play backing melodies from a flash drive, update user timbres and auto-accompaniment styles (see above) or even instrument firmware, and copy materials recorded by a sequencer to a flash drive (or even write music directly). ), etc. Specific features in different models may be different, this point should be clarified separately.

— Card reader. A device for reading memory cards — usually, the popular SD format. By purpose, this function is similar to working with a USB flash drive (see above), adjusted for the fact that memory cards will be convenient primarily when exchanging data with a laptop — almost all modern laptops are equipped with card readers, which cannot be said about desktop PCs.

The largest number of pedals that can be connected to the Digital Piano at the same time.

Pedals are an indispensable element of equipping a traditional piano, respectively, they are also necessary for electronic analogues of this instrument. However, in stationary devices (see "Body") the pedals are made built-in (see above), so this option is found only in portable models. Also note that if a stationary digital piano has 3 pedals as standard — like in a real piano — then portable digital pianos often have fewer. This is due to the fact that a full set of three pedals is rarely required in fact, and in many cases just one is enough (especially since many instruments allow you to reconfigure its functions).

In general, it makes sense to specifically buy an instrument with three connected pedals mainly for demanding professional musicians who value the full functionality of the pedals (or the ability to tie an extended set of functions to the foot control). In other cases, this parameter is not particularly important.

— USB to host (type B). Connector for connecting a digital piano to a computer using the USB standard; in this case, the instrument plays the role of a peripheral device. The possibilities of such a connection can be different: recording live music, updating firmware, voices and auto accompaniment styles, using the digital piano as an external MIDI keyboard, fine-tuning the instrument and troubleshooting, etc.; specific functionality varies from model to model.

— MIDI out. An output that allows you to broadcast MIDI signals (MIDI events) from the Digital Piano to external devices. A MIDI signal is, in fact, a "preparation" of sound: a signal generated when a key is pressed and containing information about the note number, duration, and force of pressing. Based on this signal, the electronics of the instrument (or other device) generates the sound of a certain timbre. The MIDI output can be useful for connecting a digital piano to, for example, an external sequencer for recording, or to a synthesizer for playback in a tone that is not in the piano itself.

— MIDI thru. Output used for switching MIDI signals. The description of such signals is given above, but here we note that the MIDI thru output duplicates the signals received at the MIDI input of the digital piano. This function can be useful in some specific cases — for example, connecting several electr...onic instruments together.