The friendly honk

(Acoustical Society of America) Sound permeates the human experience and gets our attention, sometimes traumatically so. Consider the car horn. It is a widespread practical application of this noise-trauma-alert principle -- and an increasing source of noise pollution worldwide as the global traffic population grows. It also is the subject of new noise pollution research to be presented during Acoustics '17 Boston. The study introduces a new pedestrian-friendly car-horn sound identified through