Eli5 How does music from a live band for example travel through wires and digital formats yet sound exactly the same when coming out of my headphones?
In: Technology
Sound is just vibration. If you pluck a guitar string, that string will vibrate the body of the guitar, which vibrates the air, which vibrates your ear drum, which then is translated by your brain into sound.
To record sound, a microphone is substituted for your ear drum. The sound vibrates a membrane in the mic. The membrane is attached to a magnet suspended in a coil of wire (I’ll just use one mike type of this example). When the magnet movies, it creates current – how much current is based on how membrane moves. This process can also be reversed – you can use current to move a magnet at the other end, which can move a membrane and make vibrations in the air. This is how a speaker works.
Recording just takes snapshots of the current in the wire periodically and records the values of the current as computer data. This is known as the sample rate – how often it takes a snapshot of the current. Again, this process can be reversed – you can use those snapshots to produce current in the wire, which is used to drive a speaker. That is how playback works.
So, it is all about taking a vibration and converting it to current, then converting that current to data (and reversing the process).
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