Comparison Casio CT-S500 vs Casio LK-S450

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 presence of a backlight in the design of the keyboard.

Usually, in this case, the illumination of each individual key is implied. This function is not of great importance for ordinary music-making, but it can be very relevant when learning: the instrument can highlight the keys that need to be pressed at the moment, simplifying the task for the student. Actually, the presence of a backlight is most often just a sign of the presence of a training mode in the instrument (see below), although not every “training” synthesizer has this function.

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 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.

The number of pedals that can be connected to the synthesizer at the same time.

Pedals are additional controls that expand the capabilities of the instrument. One of the most famous pedal functions, familiar to many from classical pianos and grand pianos, is “sustain”, where the sound continues to sound after the key is released, slowly fading out. However, the matter is not limited to this, the purpose of the pedals can be very diverse: enabling or disabling additional effects, switching between octaves or keys, etc. At the same time, in some synthesizers, mostly inexpensive, the assignment of the pedals is fixed, in others it can be reconfigured to fit your goals.

For most instruments, one pedal is sufficient, but high-end models such as workstations (see "Type") may support multiple connections.

Rated power of the built-in acoustics of the synthesizer.

This indicator characterizes, first of all, the volume at which the instrument's built-in speakers can sound. At the same time, one should not forget that in most cases such speakers are intended rather for individual use — so that the music can be heard by the musician himself and the people in close proximity to him. With this application, high power is not needed for normal hearing; and if you still need a loud sound, you can connect the instrument to an external speaker.

Therefore, it makes sense to pay attention to the power of the built-in acoustics if the synthesizer is planned to be used for more serious tasks than individual listening, and if external acoustics may not always be available.