With the CASIO AP-650, you feel like you're playing on an acoustic piano. The keys with weighted hammer action feel and play just like the keys of a grand piano. This allows you to easily distinguish your soft keystrokes from harder ones and lets you play with more emotion. Each key includes 3 sensors that measure how hard you strike the key. The sound adapts accordingly, which means the piano produces high-resolution audio. The piano comes with a sturdy underframe. The underframe has 3 pedals to sustain keystrokes or make them sound softer.