Modulation effects are a type of audio effect that modify sounds in a peculiar way. You can alter sounds with modulation effects by adding a time-delayed version of the sound itself while varying the size of that delay over time. In general, modulation provides a sense of dimension, motion, and depth. Modulators, also known as control signals, allow the user to control how a sound changes, as well as at what rate it changes. Basic modulation effects work by copying an incoming signal and modulating that copy. The reason is that the copy mixes with the unaffected sound signal. When this happens, phase shifts arise, creating an effect on the overall sound.
Modulation Effects: Types
There are various types of these effects. Here we’ll provide some of them, but the rest you can consult on our following entry on the topic.
LFOs
Firstly, low-frequency oscillators (LFOs) modify audio signals because they produce frequencies that are too low to be perceived by the human ear. They include parameters such as rate, depth and waveshape. In contrast, modulation effects include parameters such as dry/wet, feedback, chorus, flanger, and phaser.
Chorus
Secondly, the chorus effect adds richness and thickness movement to an audio sound. This effect changes the overall feeling of any given sound. There are several types of chorus effects, including mono, stereo, multi-voice, as well as the complex and multi-band.
To begin with, mono chorus operates with a mono input or sums stereo input. Then, stereo chorus operates by working on the left and right stereo inputs separately, as it outputs the two channels individually. In addition, the multi-voice chorus uses a wide variety of delays to create more complex sounds, as well as wider stereo images. Finally, the complex and multi-band chorus can produce peculiar textures.
These devices have advanced features, such as the ability to divide a sound into separate filtered bands and chorus them in an independent way. But beware: the effect produced by complex and multi-band choruses is not always pleasant to the human ear.
Flanger
Thirdly, the flanger effect occurs by gently pushing down on the flange of an analog tape recorder. When this happens, a spacey, underwater texture emerges. And, sometimes, it can mimic an exotic robot-like effect. The flanger effect occurs at short delay times. Flangers have additional parameters, such as jet and jet phase. The jet feature determines the intensity of a tremolo effect on the flanged signal, while the jet phase feature determines the phase offset of the tremolo generator compared to the modulator that is producing the flanging.
Phaser
The phaser effect splits the audio signal into two identical copies. One of the signals is modulated and then mixed with the other one. The phaser shifts the phase and does not delay the copied signal. As a result, an audio signal involving anti-nodes and nodes generates. Furthermore, the phaser effect has additional parameters, such as stages and phase difference. Stages, also known as modes, implements the delays, while phase difference determines the difference between the starting point of the left and right channel’s waveform. Using phase difference is a very simple way to achieve a sense of stereo expansion.
Modulation Effects
As you can see, there are plenty modulation effects that you can include in the creation of your tunes. For learning more about the types there are, go now to “Modulation Effects Part 2.”
