Can you hear blood flowing in an anechoic chamber?

The anechoic chamber is a laboratory built by people to simulate a free sound field. It is an amazing space that allows sound to have nowhere to hide. But in this special environment, can we hear the sound of blood flowing in the human body?

1. The mystery of the anechoic chamber

An anechoic room, also known as a soundproof room, is an experimental environment that can effectively eliminate external sound interference. Walls, ceilings and floors are constructed of special materials that absorb almost all sound waves, minimizing indoor noise.

2. The sound of blood flowing

Blood flows in the human body due to the beating of the heart and the contraction and relaxation of blood vessels. This process produces sound, but why can’t we hear it at ordinary times?

This is because the sound frequency of blood flow is lower than 20 Hz and is an infrasound wave. The hearing range of the human ear is 20 Hz to 20 kilohertz, and infrasound waves below 20 Hz cannot be perceived by the human ear.

3. Try it in an anechoic chamber

In the anechoic chamber, external noise is greatly reduced. Can people hear the sound of blood flow?

In fact, even in an anechoic chamber, we cannot hear the sound of blood flowing. Because the sound of blood flow is not only too low in frequency, but also very weak in amplitude. In contrast, environmental noises such as heartbeat and breathing are easier to detect.