If you’re judging based on what it sounds like when the captain talks to the passengers, you cannot make the conclusion that the **Mic** is what’s bad. The **Mic** might be just fine if the passenger cabin **Speakers** are the reason it sounds bad. And those speakers would be the least important thing to make easy to hear. It’s a lot more important for the crew to speak with air traffic control, and with other planes than to speak with the passengers, so it’s entirely possible the passenger cabin speakers aren’t up to the same standard.
Also remember a passenger plane is equipped with several loud white noise generators that never stop called “jet engines”. They’re going to make *every* sound wave that goes through the cabin air harder to distinguish. The white noise is at a high frequency which makes it take mental strain to have your brain’s auditory processing ‘strip’ the noise and pick out the signal.
Meanwhile up in the cockpit, the crew is wearing headsets, not hearing things through the noisy air like the passengers are.
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