A gas turbine engine (202) including a secondary fuel stage (218) which also functions as a dual frequency resonator. The engine includes a combustor (210) and a casing (205) enclosing the combustor to define a volume (214). The secondary fuel stage includes a nozzle (217) sized to be effective as a transverse resonator at a high frequency. The nozzle and the volume (214) of the casing are sized to be effective as a longitudinal resonator at an intermediate frequency.
STATEMENT REGARDING FEDERALLY SPONSORED DEVELOPMENT
 Development for this invention was supported in part by Contract No. DE-FC26-05NT42644, awarded by the United States Department of Energy. Accordingly, the United States Government may have certain rights in this invention.