MIDI controller with 49 keys. The iRig® Keys I/O series evolves the concept of traditional controllers as the only one available on the market that integrates 25 or 49 full sized keys together with a fully-fledged professional audio interface featuring 24-bit audio up to 96kHz sampling rate, balanced stereo and headphone outputs, plus a combo input jack for line, instrument or mic input (with Phantom power.). Together with an audio interface, iRig Keys I/O also packs all the controls you would expect from a premium controller including velocity sensitive multicolored pads and programmable touch-sensitive sliders, buttons and knobs for unique expressiveness and fast workflow. Both iRig Keys I/O 25 and 49 are also the smallest full sized keys on the market making them the best solution for working in small spaces and ideal when it comes to having a controller for traveling musicians, in addition to the consideration that they are the only truly mobile devices that can also work on AA batteries. Having a professional 24-bit / 96kHz capable complete audio interface built-in with iRig Keys I/O presents many advantages versus regular controllers for today's musicians.