Here's a video that solo's the various tracks from the multitrack of the song.
1) Listen how the drums groove, especially the hi-hat. It appears that there are several drum tracks, but they all groove hard.
2) I'm not sure if there are 4 or 6 tracks of clavinet, but you can hear that some of them have a lot of processing on them (as indicated in the article). Some are almost a double but have a very different sound.
3) The bass is Stevie's signature synth sound, but also the way he plays it, which is nothing like a real bass player would play it (which, of course, he isn't, nor is trying to be).
4) The horns are really compressed, out of tune at times, and have a few rough edges, but they work in the track!
5) Like most hit songs, you can hear how the track almost mixes itself at the end of the song.
Since the clav parts have had keyboard players baffled since the song came out, the second video is somewhat of a breakdown of the parts.
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