Rock and roll star Bill Haley was born exactly 95 years ago today. He sold over 60 million records worldwide, but is probably best known for "Rock Around the Clock".
The song follows a standard 12-bar blues progression and is a great introduction to the form.
In the key of A, the chords are:
A7 - A7 - A7 - A7
D7 - D7 - A7 - A7
E7 - E7 - A7 - A7
See the video below to see how to comp using just two simple shell voice "grips" (one for A7, and another for D7 and E7):
It's a lot of fun comping along to the original song. The 12-bar blues progression starts after the intro, when Bill sings "Put your glad rags on".