Number of keys
The number of keys provided on the digital piano keyboard.
The immediate range of the instrument depends on the number of keys — that is, the set of notes that can be played on it without resorting to octave transfer or transposition (see below). Most digital pianos have
88 keys, the same number as a regular piano; thus, the ranges in electronic instruments most often match those of real pianos. However, smaller models are also produced — usually
61 or
73 keys (as in most synthesizers). This number of keys is found in two types of digital pianos — in inexpensive entry-level models and in some professional instruments designed mainly for "genre" music (rock, gospel, etc.), and not for classical piano parts.
Built-in acoustics
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.
Power consumption
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".
Operating hours
Operating time of the tool from an independent power source (see above). It is worth noting that most manufacturers indicate the maximum time: at a relatively low volume, minimal use of additional functions (or at all, provided that they are not included), etc. Also, keep in mind that most digital pianos use self-
powered batteries such as AA batteries, and these batteries can vary in capacity and overall quality. However, in general, this indicator makes it possible to assess the battery life of the tool.