Why can’t the receiving end of calls hear themselves if they’re on speaker?

Question

I have no clue as to how this works on phones and computers. If noise making noise, why noise not go through to other side?

In: 0

Answer 1

There’s some techniques for preventing this. Here’s a few:

* The application uses noise cancellation, essentially trying to detect the sounds it’s making and ignoring them. This is not always perfect.
* Reducing transmit sensitivity when playing audio, so when you’re hearing sound the threshold for “send” is higher.
* Using a microphone with good off-axis rejection- meaning the pickup pattern of the microphone makes it only able to effectively pick up sound from specific locations around it- most mics with this can pick up excellently from in front but are essentially deaf to sounds to the side or behind.