Customize sounds, settings and play music from your smart device via the new Bluetooth® Audio & MIDI - WU-BT10 Bluetooth dongle The speaker system in the Privia PX-S1100 is based on a powerful membrane that provides rich high tones and an improved design that provides greater dynamics in the deepest registers. The end result is a more well-balanced sound with an extreme degree of lifelike reproduction. Casio's keys are based on a smart weighted hammer mechanism that gives the same feeling as a grand piano, although adapted to the compact format. Each of the 88 keys has its own balanced feel and timing for sound and damping, further enhancing the grand feel.