Yamaha GS1 is a digital keyboard that combines digital technology with a musician-oriented design. It features 16-voice polyphony, a velocity-sensitive keyboard, and a wide range of sounds, from piano to violin to trumpet to analog synthesizer. The GS1 also has a variety of performance controls, including vibrato, tremolo, ensemble, detune, and touch response. These controls allow you to add expression and nuance to your playing. The GS1 is also equipped with a card reader that allows you to load new voices from magnetic cards.