system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does the pitch of a sound become harder to distinguish when it is at a Lower volume?

I noticed driving home the other day, when listening to music at lower volumes the pitch of the notes the artists were singing became more ambiguous, but what they were saying was still clear. Like I could hear the words so started to sing along, but got my reference wrong and ended up in completely the wrong key. Not sure if I’ve explained that very well but I’m keen to see if anyone has any sort of explanation!
gpt
The pitch you hear has to do with how fast the note makes your eardrum vibrate. Volume has to do with how much force is behind the vibration. At high volumes there is a lot of vibration so it's easier for your brain to pick up on the pattern your eardrum is registering. At much quieter volumes there is much less vibration so it's harder for your brain to pick out this pattern; also note, at VERY high volumes the vibrations are so forceful that they can start to distort and your brain again has difficulty picking up the pattern.