Yamaha Keyboard PSR SX-900/SX900/SX 900 & Flashdisk

The Yamaha PSR-SX900 is a 61-key arranger workstation with 1337 voices, 525 styles, and a 7-inch color touchscreen. It features a joystick, assignable buttons, and a 1GB on-board memory for expansion data, along with 4GB of internal memory for songs. The PSR-SX900 also includes features like a chord looper, vocal harmony/synth vocoder, and audio recording capabilities. 
Key Features:

Keyboard: 61-key, Organ (FSB) 
Voices: 1337, including 252 Super Articulation Voices, 54 Mega Voices, 31 Sweet! Voices, 87 Cool! Voices, 131 Live! Voices, 24 Organ Flutes! 
Styles: 525, including 463 Pro Styles, 46 Session Styles, 10 DJ Styles, and 6 Freeplay Styles 
Display: 7-inch color touchscreen 
Controllers: Joystick, 2 assignable knobs 
Memory: 1GB on-board for expansion data, 4GB internal memory for songs 
Expandability: Voice and Style expandability with the Yamaha Expansion Manager 
Other Features: Chord looper, vocal harmony/synth vocoder, audio recording (WAV/MP3) 
Dimensions: 1017 mm (40") Width, 139 mm (5.5") Height, 431 mm (17") Depth 
Weight: 11.5 kg (25.35 lb) 
Expandability:

The PSR-SX900 supports voice and style expansion through the Yamaha Expansion Manager.
Expansion packs can be downloaded and installed to add new sounds, styles, and content.
You can also create your own expansion sets using your own sample libraries, according to Yamaha.