Notice that Kim Wilson leads off telling the band, “D minor, of course.” That’s because he’s playing not on a diatonic, but on the chromatic harmonica. On a chromatic harmonica in the key of C, D minor is the sweet blues key. Players like Little Walter and George “Harmonica” Smith reveal this fact.
I’m drawn to this video because lately I’ve been investigating playing blues on a the chromatic.
Here’s a bonus video of George “Harmonica” Smith. Notice he’s playing a big 16 hole, 64 reed chromatic harmonica.