Rays

Captain Rays (レイズ大佐) is a.

Devil Fruit
The Nari Nari no Mi is a, giving the user the ability to alter and control sound waves to an extreme extent. The fruit has the power to alter sound waves to the point where it can even destroy buildings and hurt people.

The Nari Nari no Mi allows the user to alter the sound waves of anything that makes noise and it can either silence it or make it louder. In some stronger cases, it can even create a concussion-like wave of sound, especially if the sound-level of a person's voice is altered. It also seems to give the user a heightened sense of sound and, whether it is because of it's relativity to the actual power or because the user already had, is unknown.