In our second session we looked at FM Synthesis. FM Synthesis stands for Frequency Modulation Synthesis, the name is fairly self explanatory, FM Synthesis is a process of creating sound by using different frequencies to modulate signal. Waveforms are produced by all different frequencies, after all that is how sound works, when you have two waveforms playing at once they can start to affect each other, this is what FM Synthesis is based on. In order to use FM Synthesis, you need at least 2 oscillators, but only one of them will be audible on its own as one oscillator has to act as the operator. The operator oscillator sends its audio signal to the other oscillator, sometimes referred to as the carrier oscillator. You will need to have 2 different waveforms in order for this to work, as the modulator’s job is to affect the carrier’s waveform to shape the overall sound. The modulator’s waveform is going to clash with the carrier’s and affect the sound produced. By changing the frequency, amplitude or shape of the modulator waveform you are able to control how the carrier modulator is affected and in turn, how it sounds. This is where the term Frequency Modulation comes from, instead of using filters and envelopes to change the sound of a waveform, you are using the frequency produced by a secondary waveform to change the sound.  

Ableton has a synthesiser that employs FM Synthesis called Operator. Operator has 4 oscillators available, A B C and D, you’re able to control the waveform shape, ADSR, and tune each oscillator. There is then a master filter and tuning controls that all 4 oscillators send signal to. The interesting thing about having 4 oscillators, and Ableton’s Operator specifically, is how much versatility there is when programming patches, Operator has a small icon in the bottom right corner which 4 coloured squares, these squares each represent the oscillator of the corresponding colour, by clicking this icon you can change the configuration of the oscillators resulting in some incredible new sounds.