system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What makes voices sound 20 vs. 50 vs. 80 years old?
gpt
Think of your vocal cords as if they were rubber bands. Brand new rubber bands (like when you are young)  are tight and bounce right back after being stretched. Now think of an older rubber band (like when you are old), having being stretched over and over. It doesn't have the same elasticity it once had.