Comparison Roland FP-30X vs Yamaha P-125

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 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 ability to overlay individual timbres provided in the instrument (or loaded into its memory by the user). Simply put, layering allows you to play a part on two timbres at once — for example, to complement the sound of a grand piano with the sound of a violin. This allows you to achieve a richer and more original sound.

Specific combinations of sounds can be stored in memory, however, in many models, the user himself can choose a combination of his own. However, it's ok to clarify these details separately.

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 ability to add a reverb effect to the sound of the instrument.

Reverb is the repeated reflection and decay of sound. Most of all, this effect is noticeable in vast spaces with a pronounced echo — for example, large caves; however, in any environment, the coloring of the sound characteristic of such an environment is mainly due to reverberation. Thus, this function allows you to simulate music that sounds in different rooms — for example, to give the impression that the instrument is in the hall of a Gothic cathedral, or, conversely, in a small room with soft walls. However, it is also possible to use reverberation as a classic sound effect, which is not aimed at simulating the situation and only gives the sound a specific colour.

The ability to transpose sound on a digital piano.

Transposition is a translation into another key, when each note rises or falls by a certain number of semitones. Support for this function allows you to at least "relearn" the keyboard, which is indispensable if you need to quickly change from key to key — for example, if the vocalist does not "stretch" his part and the melody needs to be lowered by at least 1 – 2 semitones. In such cases, it is enough to turn on transposition with the necessary settings — and you can play a familiar part on the same keys without learning it in a different layout. Transposition can also be applied to built-in songs (to adjust to the key of the main part), to tracks that the sequencer works with (to mix two parts in different keys), and so on.

The ability to fine-tune the digital piano for specific frequencies.

The essence of this function is generally similar to transposition — a slight shift of each note in frequency up or down. However, with fine tuning, the shift does not occur in steps (by an integer number of semitones), but very slowly and smoothly — by a certain number of hertz or even tenths of a hertz relative to the base scale. The base scale is often called "440 Hz" — this is the standard frequency of the "la" note of the first octave, according to which the rest of the scale is tuned. For a musician, fine tuning usually looks like an opportunity to set a different key frequency value — for example, 438 Hz or 441.2 Hz.

This feature can be useful for tuning the digital piano to another instrument whose frequencies change smoothly, such as a guitar. In many situations, it is easier to change the frequency settings in a digital device than to twist the strings or otherwise fiddle with complex tuning.

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.