If it takes more energy to produce a higher frequency, why do smaller animals produce higher pitched noises and vice versa with large animals?

Question

Elephants and whales produce pitches that are lower than humans can hear, meanwhile birds sing at very high pitches. Wouldn’t it make more sense for larger animals to produce pitches that accurately reflect the energy output that they’re capable of? I understand that amplitude is another factor in play – larger animals are capable of a much higher amplitude than smaller animals – but I still don’t get why bigger animals make lower pitched sounds.

In: 1

Answer 1

Pitch has more to do with the speed of vibration than the amount of energy input. Think of how smaller instruments have a higher pitch- flute is higher than a tuba; violin is higher than bass, etc. When the sound producing mechanism is smaller the sound bounces back more quickly with faster vibration making the pitch higher. The same is true in reverse- it takes more time for the sound waves to travel through a large instrument so the vibration is slower making the pitch lower. I hope this helps!