Through hearing we learn about source events: events in which objects move or interact so that they vibrate and produce sound waves, such as when they roll, collide, or scrape together. It is often claimed that we do not simply hear sounds and infer what event caused them, but hear source events themselves, through hearing sounds. Here I investigate how the idea that we hear source events should be understood, with a focus on how hearing an event relates to hearing (...) the objects involved in that event. I argue that whereas we see events such as rollings and collisions by seeing objects move through space, this cannot be how we hear them, and go on to examine two other possible models. On the first, we hear events but not their participant objects. On the second, to hear an event is to hear the appearance of an object to change. I argue that neither is satisfactory and endorse a third option: to hear a source event is to hear an object as extending through time. (shrink)