Yamaha DGX660 - 88 Key Portable Grand Digital Piano with Built-in Speakers & Acoustic Settings in Black with Dust Cover, Stereo Headphones and Frozen: Piano Book 192-note polyphony provides enough horsepower for dropout-free performances even while layering two voices, and playing two-handed sustained chords with heavy pedaling Wireless audio and MIDI features utilize Wi-Fi to stream audio and MIDI to/from an iOS device and the Yamaha instrument to integrate with compatible apps for iOS The Piano Room allows for choosing from a variety of pianos and acoustic settings to create a custom personal piano environment Special matte-black key tops are designed to absorb moisture, remaining tactile after extended use without becoming slippery Precisely sampled 9' Yamaha CFIIIS concert grand.554 voices, 205 styles.Feature-packed 88-key arranger piano