Which term is associated with the duration of sound that persists after it is initially played?

Reverb is the term that describes the persistence of sound after it is initially played. It refers to the way sound reflects off surfaces in an environment, creating a lingering auditory effect. When a sound is produced, it doesn't just stop abruptly; instead, it resonates as it travels and bounces around, leading to a series of echoes that gradually fade over time. This phenomenon is especially noticeable in larger spaces, such as concert halls or cathedrals, where the sound waves can reflect off various surfaces before dying out.

In contrast, the other options involve different concepts: EffectEndLocation and EffectStartLocation relate to the specific timing of where sound effects start and end within a piece of music, and the Filter refers to shaping the frequency characteristics of a sound but does not address the duration of sound after it is played. Thus, reverb uniquely captures the essence of sound decay, making it the correct answer.