Synthesizers Part 1:BASICS

Synthesizers are literally everywhere in music. Many readers here will have used them countless times to create their own music, this is because of how amazing they are. They can produce any sound imaginable from obnoxious farts to soaring trance melodies and even mimic the human voice.

This post is the first in a series to explain the basics of synthesis and some of the theory behind it so that anyone with a computer can make their own music.

So, lets begin from the very start.

Sound, as you all know is made of waves. To generate a sound, you need to generate waves. If you want to generate a musical note, you need to generate waves of a certain frequency.

It comes as no surprise then, to know that the very first part of a synth is the sound generator. These are often known as oscillators and any good synth will have oscillators that can produce a number of waveforms e.g. sine, triangle, saw etc.

I shall use the human voice as comparison. The vocal chords are the equivalent of the oscillator which produces the waves of a certain frequency.

From here, we have a sound source that can be played at different frequencies to make different notes. Below is a picture of what would happen if you turned the oscillator on. To begin with, it would be silent and then when switched on, a note would instantly play until the oscillator was turned off.

This would make a simple pure tone, that sounds like a long beep. 

We know music contains instruments much more complex than beeps and so further processing is needed. This involves adding more oscillators, filters, envelopes, modulations and effects. 

An example of these further processes can again be understood by looking at the voice. You can change the sounds your voice makes by moving your mouth, even when singing the same note. Different people have different sized throats and mouths and so everyone has different filters and modulations to their voice hence people sounding different.

Click here for PART 2 which will go a little deeper and begin to explain more about synthesis and how it works.