exhaust drone/harmonic resonance

Here's a few sites that talk about resonator pipes that are suppose to kill drone http://www.performancetrucks.net/fo...xhaust-resonator-tube-eliminate-drone-489463/
http://www.titantalk.com/forums/tit...-1-4-wave-branch-resonator-no-more-drone.html
http://forums.corral.net/forums/general-mustang-tech/496793-exhaust-drone-completely-gone.html
http://www.ls1gto.com/forums/showthread.php?p=8617677
http://www.ls1gto.com/forums/showthread.php?t=266903&highlight=helmholtz+resonator&page=2