Keys
The total number of keys on the keyboard.
The more keys provided in the design, the wider the instrument's own range, the more notes it can play without resorting to octave shift or transposition. On the other hand, this characteristic directly affects the dimensions and cost, and an extensive range is not required so often. Therefore,
88 -key instruments corresponding to a full-size classical piano keyboard are quite rare. But compact models with only
25 keys(2 octaves), on the contrary, are popular: for the purposes for which MIDI keyboards are used, this is often quite enough. Other common options are the
49 -key (4 octave) and
61 -key (5 octave) models; somewhat less common are
32 and
37 keys.
Pads
The number of
pads provided in the design of the keyboard.
Pads are auxiliary controls in the form of characteristic pads, usually square. The pads respond to touch, each of them can be tied to a specific sound or even a sequence of sounds. One of the most popular ways to use pads is to play drums or other rhythmic instruments.
MIDI in
Input for receiving MIDI signals from an external device such as an optional keyboard or other controller, sequencer, etc. For MIDI signals, see “MIDI Out”; here we note that such signals received at the
MIDI In input can be mixed with signals from the keyboard and output via MIDI Out or another interface of a similar purpose, or they can be sent unchanged to the MIDI Thru output. It is worth looking for a device with this input if you plan to build a complex from several MIDI signal sources and intend to use the keyboard as an intermediate link in such a system.
Connectable pedals
The maximum number of pedals that can be connected to the keyboard at the same time.
Pedals are used as additional controls to change various keyboard settings. The “classic of the genre” in this sense is the sustain pedal (see “Sustain”) — if the device has
one connector for pedals, then this will almost certainly be the input for just such a pedal. Keyboards are produced, where there
are 2 or more such inputs — in addition to sustain, you can connect pedals to them for other adjustments and effects (in particular, changing the volume).