identifying the nature or cause of some phenomenon

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality

the acoustic phenomenon that gives sound a penetrating quality