What is modulation in music production?
Before we get hands-on with examples, let’s understand what modulation in music is. Essentially, it is the changing of a sound’s properties over time. Instead of keeping parameters like pitch, volume, or tone static, modulation allows you to manipulate them dynamically. This movement can be subtle like a slight vibrato on a lead — or extreme, like a chaotic bass growl.
Modulation makes a track feel alive. Without it, synths can sound rigid, and effects might feel flat. Used correctly, modulation adds depth, motion, and variation, and can make simple elements more engaging.
Modulation applies to almost every aspect of sound design and mixing. It’s used in synthesizers, effects processing, and mixing techniques to create movement in different ways. The most common types of modulation include:
- Synth modulation: Using LFOs, envelopes, and other modulation sources to dynamically alter a synth’s sound.
- Modulation effects: Effects like chorus, phaser, and flanger that add motion to a sound.
- Frequency modulation (FM) and amplitude modulation (AM): Synthesis techniques where one waveform changes the sound of the other. These are relatively similar techniques in theory but differ in what aspects of the waveforms are used as a modulation source.
An example of synth modulation can be heard in Skrillex’s classic brostep track “First Of The Year (Equinox).” Listen to the growling synths that start at 01:27. Here Skrillex is modulating various parameters over time like wavetable position and filtering to achieve an aggressive “growl.”
