Attenuating Out Of Band Energy Emitted From Seismic Sources

A seismic source for marine seismic acquisition is described, comprising an outer cylinder having one or more apertures, an inner cylinder having one or more apertures configured to align with the apertures of the outer cylinder at one or more predetermined rotational positions of the inner cylinder, wherein an outer wall of the inner cylinder is flush with an inner wall of the outer cylinder, an axis bar coupled to the inner cylinder, wherein the axis bar rotates the inner cylinder, an actuator coupled to the axis bar, wherein the actuator controls a rate of rotation of the inner cylinder, and a gas supply coupled to the inner cylinder, wherein the gas supply provides a compressed gas inside the inner cylinder, wherein the compressed gas is released out of the seismic source such that a volume of water surrounding the seismic source is displaced at less than a predetermined rate, thereby attenuating an out of band frequency emitted by the seismic source.