How do speakers create so many layers of sound, from one or two cones vibrating. Pt 2, how do the cables carry soooo much information to a passive speaker from the amp.

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Title explains it? Passive speakers blow me away – that they are getting all of that info from two small cables from the amp. It seems incredible.

And how is there such separation and depth in the layers of music when it’s coming from more or less the same cones.

In: Engineering

>Title explains it? Passive speakers blow me away – that they are getting all of that info from two small cables from the amp. It seems incredible.

>And how is there such separation and depth in the layers of music when it’s coming from more or less the same cones.

There is no separation and there is no depth. A speaker always just plays one sound. It can change that sound quickly, vary the frequency and the amplitude but it still only plays one sound. That’s the signal it receives, that’s the sound it plays.
Everything else happens in your head. All your brain’s pattern recognition ability (that’s a violin! that’s my mother’s voice!) stems from the order and context in which that sound is played and varied. *That* is the truly incredible part, not the speaker!

First off the cables are analog, not digital, so they can potentially carry an infinite amount of information (ignoring electrical noise for this ELI5).

Next, what you hear as sound is your ears reacting to air pressure vibrating at certain frequencies. A pure tone will have one frequency and not sound terribly pleasant. A voice or instrument will have a dominant frequency but also multiples of that frequency called harmonics. Added together, they make up the sound.

The electrical signal in your cables looks exactly like the pressure wave signal of your sound. When it is applied to the magnetic coils in your speaker, it causes it to vibrate in the same pattern as the electrical signal, which makes a pressure wave also in the same pattern.

Now the same way that you can add up base frequencies and harmonics to create a sound like a voice or instrument, you can continue to add up several base frequencies and their harmonics to get a mixture of instruments in your sound. This is getting beyond ELI5, but I suggest you learn about Fourier Series. It is fascinating…actually, mindblowing…but it explains how any signal can be broken down into a series of different frequencies.

It’s part of the fundamental nature of wave math. You can add in as many layers at different frequencies as you want and they’ll super-impose and phase through each other without ever losing information. It works for light, water, sound, whatever.

In real life you hear sounds from individual things as vibrations of the air. There are many different vibrations coming from different directions, and when they hit your ear they are combined into what your nerves identify as sounds. For a speaker, all those different sounds are combined by microphones into electrical signals, that are shaped just like like air vibrations your ear recognizes. When the electrical vibrations hits the speakers, the speaker vibrates the air making the combined noise.

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