Yamaha YDP-S55 B Arius Digital Piano, 88 weighted keys with hammer action (graded hammer, GH3) and top layer with synthetic ebony and iovry, 10 sounds (incl. one high end sound sampeled from Yamaha CFX grand piano), polyphony: 192, effects (reverb: 4 types, Stereophonic Optimizer, Intelligent Acoustic Control), midi-recording (2 tracks), functions: dual, duo mode, metronome, transpose (-6 - +6), tuning (414,8 - 466,8 kHz), pedals: sustain (half damper), sostenuto, soft, connections: USB to host, 2x headphone output (6,3mm stereo jack), speaker system 2 x 20W, power supply (PA-300C) and music book ""50 Classical Music Masterpieces"" included, dimensions (WxDxH) : 1353 x 309 x 792 mm (depth with open key cover 317 mm), weight: 40 kg, color: black