The present application provides a tangentially fired boiler. The tangentially fired boiler may include a combustion chamber and an overfire air system positioned about the combustion chamber. The overfire air system may include a number of overfire air windboxes positioned in a horizontal orientation.

A damper for a gas turbine combustion chamber as shown in FIG. 1 includes a damper volume wall and a main neck. The damper volume wall defines a damper volume inside the damper volume wall. The main neck includes a main neck wall defining a main neck volume inside the main neck wall. The main neck is associated with the damper volume for fluid communication between the damper volume and the gas turbine combustion chamber. In addition, the damper includes a gap between the main neck wall and the damper volume wall. The main neck defines a main neck axis. For example, the gap is a second neck, and in further embodiments, multiple damper volumes are provided.