If you put this into your stereo system it would sound awful. You'd hear a huge buzzing noise and be very unhappy. The buzzing noise happens because there are faster changes from + to - than 60 times a second and our power supplies aren't equipped to handle these faster changes so they get added to the music we hear.
Instead what we want is a sine wave. A sine wave is the same thing you see in the picture of the square wave only with all the faster changes removed. A sine wave looks like this:
Notice how it is very gently curving up and down? That's what our power supplies in our stereo systems want.
Just to make sure we all understand this very important fact, here is a picture showing a sine wave and a square wave laid on top of each other to make the point.
Notice how the two are the "same" but different shapes? The difference is important to understand because when we convert the AC to DC to make music, one works better than the other. So shape matters.
How did this sine wave come to be and why is everything we listen to in audio based on receiving this nice, gentle waveform? Was it because of some super smart guy like Tesla invented the sine wave with purpose in mind?
No, actually it was the other way around. The nature of how AC is generated creates the sine wave and our technological society adapted everything to it including our stereo systems. Sine waves weren't invented, they are a result of a process.
Tomorrow I'll explain how and the importance of the sine wave to making music.
0 comments