The microKEY25 from Korg is a slim, lightweight (1.43 lb), 25-Key USB powered controller with tap tempo, arpeggiator, sustain and velocity-sensitive "Natural Touch" mini-keys. It is USB powered by connecting to your computer or iPad. It has been designed to maximize playability while still integrating into a compact production setup.
The microKEY25 is equipped with an expressive joystick that allows you to transmit pitch bend, modulation and control change commands to enhance your MIDI performances. When the arpeggiator is on, the functionality of the joystick changes, now allowing you to switch between the 3 different arpeggio types (up, trigger, and down), control the duration of the arpeggiated notes, and engage the latch function to continue play of an arpeggio even after you take your hand off the keyboard.
There is a Sustain/Tap button for adding sustain your performances as a sustain pedal would. When the arpeggiator is on, this control becomes a tap button that allows you to set the tempo of the arpeggio by pressing this button several times at the desired interval. The Key Transpose feature allows you to transpose the pitch of the keyboard up or down in semitone steps. Octave Shift buttons let you extend the note range of the keyboard by 4 octaves in either direction.
Edits to advanced MIDI parameters, such as the joystick control change number assignments and the keyboard's velocity curve can be made using the KORG KONTROL Editor software, available for free download on the Korg website. This can be useful in customizing the microKEY to give you greater control over a virtual instrument, or to accommodate harder or softer keyboard playing styles.