Comparison Yamaha PSR-EW425 vs Yamaha PSR-SX900

The greater the number of keys — the wider the range of the instrument, the lower and higher notes you can take on it right during the game, without resorting to tricks like octave shift (see below). By comparison, a full size piano keyboard has 88 keys. However, in synthesizers, such an amount is rare, because. the instrument would have turned out to be too bulky and expensive, and not every musician, even a professional one, needs such an extensive range. Thus, 88-key keyboards are used primarily in high-end workstations (see "Type"). For ordinary synthesizers, the standard is 49, 61 or 76 keys ( there are also options for 73 keys) — this is usually quite enough (while the "golden mean" option is considered to be 61 keys). And small children's models can have 32 keys.

Ability to change the sensitivity of active mechanics (see above) in the synthesizer.

This function allows you to adjust the intensity of the key's response to pressing. Simply put, the higher the sensitivity, the louder and sharper the sound will be, with the same pressing force. This allows you to change the characteristics of the instrument's sound.

Also in synthesizers with this function, it is often possible to completely turn off the active mechanics and play on a “passive” keyboard. This can be useful for making certain voices, such as harpsichord or organ, sound realistic.

The polyphony supported by a synthesizer, in other words, is the number of “voices” (tone generators) that can simultaneously sound on it.

This parameter is often described as the number of notes that can be played simultaneously on the keyboard. However, this is not entirely true due to the fact that in many timbres one note can activate several tone generators. As a result, for example, to play a chord of 3 notes in a timbre with 4 tone generators per note, polyphony of at least 3 * 4=12 voices is required. In addition, Auto Accompaniment and Preset Songs (see related sections) also use tone generators, requiring even more voices to work effectively with these features.

The minimum value for a more or less functional modern synthesizer is polyphony for 32 voices — and even then such an instrument can be used mainly for initial training and simple melodies. For a more solid application, it is desirable to have at least 50 – 60 voices, and in professional models (in particular, workstations where you have to deal with several audio tracks at once), there are models with polyphony for 150 tone generators or more.

In general, a more advanced synthesizer is likely to have more extensive polyphony, however, it is only possible to evaluate the class of an instrument by this parameter very approximately — instruments with the same number of voices can differ greatly in level. The only exception to this rule are children's synthesizers (see "T...ype"), which support up to 20 voices.

The number of built-in sounds provided in the synthesizer.

The number of timbres is often described as the number of instruments that a given model can imitate. However, this is not entirely true — rather, this parameter can be called "the number of instruments and sound effects." For example, the same instrument — an electric guitar — with different "gadgets" (distortion, overdrive) will sound differently, and in the synthesizer each such gadget will be considered a separate timbre. The “drums” timbre usually combines different types of drums and other percussion instruments — in other words, it allows you to portray both the “bass drum” and the cymbals without switching settings, just by pressing the desired keys. And some timbres may not have analogues among real instruments at all.

The more built-in timbres, the more extensive the possibilities of the synthesizer, the more diverse the sounds that can be extracted from it. At the same time, in high-end models like workstations (see "Type"), this number can reach 1000 or even more.

The number of auto accompaniment styles (see above) originally provided in the synthesizer, in other words, the number of accompaniment options available to the user.

The more extensive this set, the higher the probability of finding among these melodies suitable options for a particular case. At the same time, the abundance of styles in itself is not yet a 100% guarantee that among them there will be a suitable one, especially since different synthesizer models can differ markedly in a specific set of melodies. So the list does not hurt to clarify before buying. Also note that the situation can be corrected by user styles (see below) — many synthesizers with auto accompaniment support them.

The presence of a learning mode in the design of the synthesizer.

The purpose of this function is clear from the name. It is most often based on the following principle: the synthesizer itself tells the student which keys to press, displaying the keyboard on the display or highlighting the necessary keys using the backlight (if available, see above). Of course, at different levels of learning, the format of such prompts will also be different: for example, at the very beginning, the synthesizer highlights the necessary notes until they are pressed, and at the final stage it highlights them at the tempo at which you need to play the melody, and evaluates the accuracy of the student pressing the desired keys. There are also other features and nuances of learning — for example, the mode of separate learning of parts for the left and right hands, when the instrument itself plays one part and tells the student how to play the second. In addition, a metronome function is practically mandatory for a synthesizer with this mode (see below).

Regardless of the specific functionality, this mode will be very useful for those who are just developing their keyboard playing skills.

The range in which you can change the tempo of the programme played by the synthesizer — auto accompaniment, lesson tune (see above), metronome (see below), recorded sample, etc.

Pace is measured in beats per minute. Changing it allows you to adjust the speed of the synthesizer to the specifics of the situation — for example, slightly slow down the tutorial if it is too hard to master at the initial pace. The wider the range of tempo adjustment, the more options the musician has to choose from, especially in the area of very slow and very fast tempos.

Note that the traditional range of musical tempos covers values from 40 beats / min (“grave”, “very slowly”) to 208 beats / min (“prestissimo”, “very fast”), however, in synthesizers it can be more extensive — for example, 30 – 255 bpm.

The presence of a mixer in the design of the synthesizer.

A mixer in this case is a device designed to control individual audio channels that make up the sound of a synthesizer as a whole. The list of these channels includes, in particular, the main voice, the layered voice (see “Dubbing voices”), several auto accompaniment channels (main, bass, drums, etc.). With a mixer, the musician can manually control these channels — turn some of them on and off, switch the timbre, tempo, key, etc. This greatly expands the possibilities for using the synthesizer.

Synthesizer support for octave shift function.

This function allows you to shift the sound of the instrument one or more octaves up or down — for example, so that the keys of the first octave sound the notes of the second, or vice versa. This function can be used for both simple convenience and more practical purposes — it allows you to play very low and very high notes that are not initially covered by the keyboard range. This is especially useful for shortened 49- or 61-key synths that do not initially fit the full range of the piano.