Aluminum Cylinder "First Cylinder" - Wil Strijbos

The object of the puzzle is to open the cylinder. As you'd expect with a Wil Strijbos puzzle, this is a challenge. Sound is important when attempting to solve this, but you're essentially operating in the blind.
A seriously well crafted puzzle milled from solid polished aluminium, Wil is world famous in the puzzle community for the complexity and quality of his collection. it's important to note that he does not provide solutions with his puzzles.