Question about how analog audio recording works

https://en.wikipedia.org/wiki/Phonograph_record

maynovent

... when you're talking several sounds at once, some on the same pitch some now, dozens of timbres happening all at once, how do we differentiate those sounds on a physical medium like vinyl, or how do we represent it digitally ...

It's the Fourier Theorem. The same math that makes the 1s and 0s work in digital also explains the squiggly grooves in an LP.

@maynovent - I've wondered this same thing about speakers. How does a single driver replicate sounds of different freq. at the same time without stepping on itself and smearing one or the other? 

dweller

I've wondered this same thing about speakers. How does a single driver replicate sounds of different freq. at the same time ...

Again, it's the math of the Fourier Transform, that a continuous function (such as an audio signal) can converted to a form that represents the sum of a series of terms.

In air, there's no such thing as polyphony.  Air pressure is either rising or lowering. The sound of a violin, or drum, or any complex sounding instrument at any instant in time is creating pressure at a microphone which is either going up or going down or still when silent.

That up and down is what a vinyl record tracks, and what a speaker driver represents as it moves towards you or away from you.