Words4EV.speak 1.0 (en)

Drumming is an ill-defined sound, very low-frequency, high in level and erratic. One may say it keeps a beat, similar to a drum or timpani. Drumming corresponds to a "rolling" sound where the dull aspect has been pushed to an extreme with an erratic impacting component. It causes physiological disturbance that is extremely uncomfortable with a pressure sensation in the ears recalling "humming". Drumming occurs at low speed on an identified range of speeds between 10 and 50 km/h on a type of road surface with specific solicitation (e.g., bad surface or pavement roads).