Polyphony
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.
Built-in timbres
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.
User timbres
The number of memory slots for user tones provided in the synthesizer.
For Voices in general, see “Preset Voices” above. User timbres are sound settings that were not originally provided in the synthesizer's memory and are created by the user according to their preferences. This feature is indispensable in cases where the built-in set of timbres does not contain the necessary options. However, the capabilities of the User Voices may vary from model to model. So, one instrument only allows you to edit and supplement existing timbres (for example, add a “wah-wah” effect to a bass guitar and save such a bunch as a user setting), another makes it possible to set the sound parameters almost manually, and the third even allows you to load timbres through USB (see below).
The more user timbres in the synthesizer, the more personal “instruments” you can register in its memory.
Accompaniment styles
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.
Custom styles
The number of user auto accompaniment styles supported by the synthesizer, in other words, the number of additional styles that can be stored in memory in addition to the built-in ones. Note that styles can have different volumes (depending on the number of notes used), so this parameter often turns out to be not exact, but only an average-approximate one.
Modern synthesizers may have a fairly extensive set of built-in auto accompaniment styles (see above), but even the richest set may not contain the desired melody. Thus, many models allow you to supplement the standard list with custom melodies. The addition methods themselves can be different: in some models, these melodies need to be downloaded from external media, in others they can even be composed manually. Nevertheless, the presence of user styles allows you to expand the range of auto accompaniment melodies, moreover, at the request of the user himself.
Learning mode
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.
Octave shift
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.
Arpeggiator
The presence of an arpeggiator in the design of the synthesizer.
The term "arpeggio" originally means the technique of playing a chord, in which the notes are not sounded all at once, but one after another. Accordingly,
arpeggiator, roughly speaking, is a device for the automated playing of chords using the arpeggio technique. Compared to manual playback by notes, this function is convenient because the arpeggiator can provide various additional settings: set the direction of playback (up or down), speed, interval between notes and their duration, special effects, background accompaniment, etc. At the same time, all effects work automatically, the user only needs to press the keys that make up the chord (and in some synthesizers in some modes, only one key can generally be responsible for a whole chord). The specific capabilities of arpeggiators can be different, often such a device allows you to create entire compositions just by pressing a sequence of chords.
Pitch controller
The presence
of a pitch controller(Pitch Bend) in the design of the synthesizer.
This function allows you to smoothly change the pitch by a small amount. In this way, specific playing techniques on some instruments are imitated — for example, tightening the strings on a guitar, which gives a characteristic, “floating” sound in frequency. The pitch control usually has the form of a wheel or lever.
