Hi. I am Darran Kelinske from Austin, TX in the USA. This lesson is for Week 5 of Introduction To Music Production at Coursera.org. This week I will be teaching you about the Flanger and Chorus effects. Both of these effects are considered to be modulated short delay effects.
In this lesson we will be using the following recording as a sample.
What is a Flanger?
A Flanger is an effects unit which produces flanging. According to Wikipedia flanging is:
“an audio effect produced by mixing two identical signals together, one signal delayed by a small and gradually changing period, usually smaller than 20 milliseconds.”
Said differently, a Flanger produces an audio effect by combining an audio signal with an identical audio signal that has been slightly delayed. When the signals are combined, the frequency response of the combined signal is different than the original signal due to constructive and destructive interference created by the addition of the delayed signal. The amount of delay applied to the delayed signal is varied over time. This variation in delay creates the flanging effect.
Flangers typically produce an audio effect that is described as a “jet plane-like”. To me, they produce an airy sound when used in moderation, but can produce psychedelic sounds when setting parameters to their extremes.
A screenshot of the Ableton Live Flanger effect is pictured below.
Listen to the audio clip below to hear the default Flanger settings applied to our original audio clip.
The Delay Time setting on a Flanger specifies how long to delay the audio signal that is being added to the original audio signal. During my experimentation I’ve found that higher delay times typically produce more unconventional sounds.
LFO (Low-frequency oscillator)
The LFO is responsible for varying the amount of delay that is applied to the signals that are added to the original signal. The Flanger in Ableton uses two parallel time-modulated delays to create flanging effects. One of these delays is for the right channel and one is for the left channel. Because of this, you can hear the sound moving from side to side in your headphones while the Flanger is in effect.
The LFO in Ableton Live has a few settings which include Shape, Amount, Rate, and Phase.
The Shape settings specifies the shape of the modulation and includes sine, square, sawtooth, and random options.
According to the Ableton Live manual, the Amount parameter specifies “the extent of LFO influence on the delays.” Experimenting shows that the Amount to 0% results in 0% modulating of the time delay. Increasing the amount results in greater variations in time delay.
The Rate setting is responsible for controlling how often the LFO waveform repeats itself. Note: I found this easy to understand description from canadianmusicartists.com here.
Lastly, according to the Ableton Live manual the Phase setting behaves in the following manner:
“The Phase control lends the sound stereo movement by setting the LFOs to run at the same frequency, but offsetting their waveforms relative to each other. Set this to ”180”, and the LFOs will be perfectly out of phase (180 degrees apart), so that when one reaches its peak, the other is at its minimum.”
The Feedback setting controls how much of the output signal is sent back into the input signal.
Similar to other effects, the Dry/Wet knob determines how much of the output signal is composed of the original signal (dry) and the processed signal (wet).
A full description of the Ableton Live Flanger Effect can be found in the online manual here: https://www.ableton.com/en/manual/live-audio-effect-reference/#flanger
What is a Chorus?
A Chorus is an audio effect that is typically produced by “taking an audio signal and mixing it with one or more, pitch modulated copies of itself.” Source: Wikipedia
Using a Chorus effect can make an audio signal sound more full. This is due to the original signal and copies of the signal combining to be perceived as one full sound as opposed separate distinct sounds.
The Chorus in Ableton Live appears to be comprised of two delay units. Each of these delay units can have differing delay times that are modulated according to settings available in the effect unit.
A screenshot of the Ableton Live Chorus effect is pictured below.
Listen to the audio clip below to hear the default Chorus settings applied to our original audio clip. The clip will sound a little brighter because the default effect setting includes a high-pass filter which filters out much of the kick drum.
The delay time is found at the bottom of each delay unit and specifies the amount of delay that will applied to the audio signal.
The delay time for each delay can be modulated using the Modulation settings. The modulation settings include the Amount which determines the amount of modulation that will be applied to the delay and Rate which is the rate at which the modulation will occur.
Similar to the Flanger effect discussed earlier, the Chorus effect has a feedback setting which allows the processed signal to be sent back into the input signal.
The Chorus plugin has a Dry/Wet knob which allows you to specify how much of the output signal is comprised of the original (dry) and processed (wet) signal.
I found a good overall description of the Ableton Live Chorus plugin here.
Additionally, the full description of the effect can be found here: https://www.ableton.com/en/manual/live-audio-effect-reference/#chorus
In this post, we reviewed the Flanger and Chorus effects that are available in Ableton Live and how some of the parameters in the these effects impact sound.
While this lesson is very basic, many of the ideas and facts covered in this lesson were knew to me.
If there are any inaccuracies or if there is any feedback you have to provide, please contact me through Coursera or social media. Thank you for reading.
Ableton Project File:
The Ableton Live Project used for this post can be found here: UsingFlangerChorus Project