Yamaha P45B Digital Piano with Single-X Keyboard Stand GHS weighted action is heavier in the low end and lighter in the high end, just like an acoustic piano. Advanced Wave Memory Stereo Sampling recreates natural instrument sound in stereo. 64-note polyphony allows the player to perform moderately dense piano passages, even using heavy sustain pedal, with few or no dropped notes being cut off. Dual Mode lets you combine two Voices together, like piano and strings, for an inspiring new playing experience. The USB to HOST port allows you to connect and interact with a wide variety of educational, music creation or music entertainment applications on a computer or mobile device.