Comparison Casio Privia PX-870 vs Casio Privia PX-770

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 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.

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.

— 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 number of line outputs provided in the design of the digital piano.

The line output allows you to send the sound from the instrument to external audio equipment. In this case, the sound is transmitted in an analogue format, and to play it, it is enough to pass it through a power amplifier; and active acoustics can generally be connected directly to the line output. The outputs themselves can use different types of connectors, but most often they are 3.5 mm mini-Jack or 6.35 mm Jack, compatible with most audio equipment either directly or through the simplest adapters.

Multiple line outputs allow you to connect multiple signal receivers to the instrument at once — for example, speakers with an amplifier for playback and an external recorder for recording. However, digital pianos rarely have more than 2 line outputs — more, taking into account the specifics of the use of such instruments, is simply not required.

The power of the native acoustics installed in the Digital Piano.

This indicator directly affects the maximum volume that the instrument is able to produce "on its own", without connecting external speakers. At the same time, it is worth noting that many manufacturers go to the trick and indicate in the characteristics not the rated power (rms power when operating at full volume), but the peak power, which is the highest power that the acoustics can deliver at short “ups” of volume. Peak power values can be quite impressive — in the tens and hundreds of watts — but these figures have a very indirect relation to the actual capabilities of the speakers. Therefore, before choosing, it is worth clarifying what kind of power is mentioned in the characteristics. To do this, it is not necessary to look for detailed data on the instrument, it is enough to compare the power of the speakers with the power consumption (see below): if the claimed power of the acoustics is greater than the power consumption of the entire instrument, then the manufacturer indicated exactly the peak value.

The power consumed by the tool during normal operation.

The cost of electricity, as well as connection requirements, depend on this indicator. At the same time, we note that digital pianos require relatively little energy — even in the most powerful and advanced models, consumption usually does not exceed 60 watts. So in fact, power consumption data is required mainly for specific cases — for example, to calculate the total load when connecting a tool to an autonomous generator along with other devices. In addition, this information may be useful when assessing the power of the built-in speaker, for more information, see "Built-in acoustics".