Timbre refers to the character, texture, and colour of a sound that defines it. It's a catchall category for the features of sound that are not pitch, loudness, duration, or spatial location, and it helps us judge whether what we're listening to is a piano, flute, or organ
The Tell Tale Heart is a good coparison of some challenges many eighth graders might face. Including, the guilt of lying or deceiving someone and being extremely annoyed by someone or something.