When 90dB is LOUDER than 120dB

TL;DR

Decibels measure sound wave height, not loudness, which depends on frequency.

Transcript

If you were locked in a room with a pair of  speakers and had to choose between a sound   measuring 90 decibels or one measuring 120  decibels, you’d probably pick the one with   fewer decibels. I mean, a less loud sound would  surely be less painful, right? But you might have   just picked the very loud sound of a crying baby  over the very quiet ... Read More

Key Insights

• 👋 Decibels measure sound wave height, not loudness.
• 👂 Sound perception is influenced by frequency, not just decibel level.
• 🧡 Human ears are most sensitive to mid-range frequencies.
• 🔊 High and low frequencies may not be perceived as loud due to lack of specific hair cells.
• 👂 Decibels are used as an approximation for loudness of common sounds.
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Questions & Answers

Q: How do decibels measure sound?

Decibels measure the height of sound waves, not loudness, which is influenced by frequency. Human perception of sound relies on more than just wave height.

Q: Why are human ears most sensitive to mid-range frequencies?

Human ears are most sensitive to mid-range frequencies because of how hair cells in the ear resonate with different sounds, with stiff hairs for high frequencies and bendy hairs for low frequencies.

Q: How does sound perception differ for high and low frequencies?

High and low frequencies may have high decibel levels, but if they fall outside the range of frequencies our ears are sensitive to, they may not be perceived as loud due to the lack of specific hair cells in our ears.

Q: Why are decibels commonly used to measure loudness?

Decibels are used to measure loudness as a general approximation for sounds that we are sensitive to, even though they technically measure sound wave height, because most common sounds fall within our sensitivity range.

Summary & Key Takeaways

• Decibels measure sound wave height, not loudness, which is influenced by frequency.

• Human ears are most sensitive to mid-range frequencies, like a baby's cry.

• Decibels are a good approximation of loudness for sounds we are sensitive to.