The Yamaha DGX-620 is the name of a digital piano (also known as the YPG-625). The lettering DGX encompasses the word Digital Grand whereas YPG stands for Yamaha Portable Grand. It was released by Yamaha Corporation in late 2006, the first model of the DGX/YPG series with weighted keys.
The DGX-620 is an improved version of the earlier Yamaha DGX-520 keyboard. In June 2008 the Yamaha DGX-630 replaced the DGX-620 (aka YPG-635). Its successor, the Yamaha DGX-640, was released in 2010, being the most piano-like model in the series. In 2013, the DGX-650 Digital Piano was released and is now the flagship model of the Portable Grand series.
The Yamaha DGX 620 keyboard is very natural-sounding and reliable. It does very well with the rendering and voicing of General MIDI files. It also has the ability to show the score of the song and allows the user to learn from existing midi files.