Energy density and impact rate jointly explain small-room acoustic behavior

Evidence

Another way of visualizing this is to realize that in a smaller room, there is less volume for a given amount of sound energy to spread out in, like a pat of butter on a smaller piece of toast. Therefore the energy density, and thus the sound level, must be higher in smaller rooms. However, there are more impacts per second with the surface of a smaller room, which gives rise to the more rapid decay than in a larger room. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1767

Categorization

• DEFINE: The butter-on-toast analogy clarifies why energy density must rise in smaller enclosures.
• SHARE: A great analogy to send to anyone who mixes music in a small untreated room and wonders why it sounds boxy.