If there is a headwind, the sound will sound louder to the other party. Consider the nature and principle of sound.
【’It is easier for voices to be heard if they are shouted against the wind!’ Find out why we feel this fact is backwards.】
・Research by Ville Pulkki, acoustician at Aalto University, Finland
・Reported that “shouting upwind makes one’s voice louder,” but that “it is harder for the person shouting to hear himself.”
・Acousticians have long known that shouting from downwind to upwind amplifies the voice.
・Acoustic measurement experiments have shown that sending a sound source upwind increases its amplitude and sending it downwind decreases its amplitude
・It indicates that a voice shouted from downwind to upwind will be easier to be heard by those upwind, but harder to be heard by the person who shouted (“If you shout from downwind to upwind, your ears will be behind your mouth, that is, downwind, so the sound your ears receive will be less.”).
These are the quotes from the article
Sound affected by wind. Consider the nature of sound with the vibration image of air.
A voice shouted from leeward to windward will be heard louder by those on the windward side (the other side will hear your voice louder if there is a headwind).
At first, I thought, “Hmm? but when I thought about it calmly, I understood.^^
I recall writing the following blog a long time ago.
【Temperature, humidity, upwind, downwind, etc., do not allow sound to travel in a constant manner.】
・Tailwind makes the sound faster, headwind makes the sound slower.
・Warm air makes the sound faster, cold air slows it down.
・Highs go fast in a straight line and lows go slow without a sense of localization (directionality)
・Sound transmission is not constant.
I have written about the above in past blogs,
“A tailwind makes the sound faster, a headwind slows it down.”
From this part of the study, it would seem that a tailwind would be louder to the other person. But the study above reports that a tailwind makes the voice quieter and a headwind makes it louder.
Interesting. Now, let’s imagine. Sound is a wave. We can also say that it is a vibration of the air, a wave. (Sound can also be transmitted by liquids and individuals.)
If there was a headwind, don’t you think that the wind coming toward you would compress and crush these waves so that the waves above and below would be higher? The ups and downs of the waves represent the loudness of the sound. In other words, the sound becomes louder.
The headwind is the opposite. A wind coming from behind is going to flatten this wave and make the waves up and down smaller. In other words, the sound will be reduced.
I understood the above study with this image. Did you get the image?
Once again, I will summarize.
Tailwind makes the sound faster but quieter
Headwind slows the sound but makes it louder
The reason it is difficult to hear oneself in a headwind is partly because the wind hits the ears, but also because, from the mouth’s perspective, the ears are in a tailwind, and therefore one’s voice is muffled.
One point that concerned me was about the distance that sound (voice) can reach.
The study above expresses that a headwind makes your voice louder and therefore easier to reach, but I have some doubts about that.
The headwind may make the voice louder, but it slows the voice (sound) down, and I feel that the distance will not be as great because of the compression up and down.
On the other hand,
In the case of a tailwind, the voice will be quieter, but the voice (sound) will be faster, and thus the distance should be greater.
Which sound is more distant, the slow sound that has been compressed and made louder, or the fast sound that has been flattened and made quieter? Which sound reaches people farther away?
I am curious. (offset by all sorts of things, maybe about the same?)
Once again, sound is interesting.
I was a musician who thought so.
See you then.
Be careful how you speak up when there is a headwind or a tailwind. It may sound louder or quieter to the other person than you think.research