Is that main line from Superstition by Stevie Wonder a slap bass line? I can hear the bass underneath it, but did they multi track another "lead" slap bass line into the main riff? Also, what other songs are like this, and Signed Sealed and Delivered, have great basslines?
its a clavinet .. a type of keyboard.
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Pretty sure it's Stevie's keyboard. Nate is probably playing the same thing under it, however. Sir Duke, I Wish, Do I Do- anything with Nate Watts on the track has an awesome bassline.