It uses a large collection of audio samples taken from three grand pianos.
The software used for playback is Native Instruments' own Kontakt Player (a feature-limited version of Kontakt), which is used as a stand-alone program for live performance or recording to MIDI.
The Kontakt synthesizer includes several optional transformations to the sample's sound.
Pitch level, pitch bend, velocity curve, tuning system (including quarter-tone), dynamics, microphone distance, equalizer, lid position (closed, half-, or full-stick) as well as choice of performance space may all be modified.
Akoustic Piano is now a Macintosh Universal Binary.