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.

Question

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

Answer 1

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.