Though Chaka Khan was first to record this way back in 1978,
here's an instrumental rendition of the 1992 Whitney Houston hit "I'm Every Woman"
performed by Petry Giles on his Korg Kronos and Tyros 4.

Production details: He utilizes a modified midi file.
Bass, drums, Guitar Piano are Korg Kronos voices.
Choir, Strings are Tyros 4 voices
The 2 keyboards are midi connected and the midi file
is played by the Tyros 4.