While all modulation effects share some similarities, each one of them can bring to life distinctive soundscapes, whether you use them on stage or in the studio as plugins.
Today we’ll take a look at two of the most popular (and often confused) effects: the flanger and chorus.
These two time-based effects have been part of guitarists’ pedal boards since the 1970s, and defined eras of music across all genres. So let’s find out more about them!
What’s a Chorus?
Chorus is probably the most famous modulation effect there is, probably because it was literally everywhere in the 1980s.
The name says it all: the chorus effect creates the illusion of multiple guitars playing the same note, just like voices in a choir. It does that by adding a slightly delayed version of the original signal and subtly modulating its pitch over time. The delay time is usually between 20 and 50 ms. The result is a warm and lush sound that makes the guitar sound more immersive and three-dimensional.
The Roland JC-120 guitar amp was the first to feature a built-in chorus, back in 1975, and was so successful that it’s still produced today. By the mid-1970s, BOSS and other companies started introducing dedicated chorus pedals in the market, making the effect more accessible to guitarists and producers.
You can listen to it here:
What’s a Flanger?
The unmistakable “whooshing” tone of the flanger effect is created by combining the original signal with a slightly delayed version of itself (usually under 15ms).
As the delay time modulates, the two signals create a series of peaks and notches in the frequency spectrum. The result is the sweeping, jet-like sound the flanger is mostly known for.
While more recent in its pedal form than the chorus, the flanger effect was invented earlier. Les Paul discovered the effect in the late 1940s, and soon after, sound engineers like George Martin created it in the studio by manually pressing a finger on the tape reel flange to create timing differences between two audio signals.
You can listen to it here:
The Main Differences in a Nutshell
To the untrained ear, chorus and flanger effects may sound similar because both involve delaying and modulating an audio signal.
However, once you listen to them carefully, it’s easy to notice how different they are:
- Chorus effects use longer delay times (20-50ms) than flangers (15ms or less).
- The delay line of a flanger creates notches and peaks in the frequency spectrum through comb filtering. The chorus does not.
- A Chorus produces a rich, harmonic series that sounds smooth and natural, whereas a flanger has a distinctive jet-like texture.
- A Chorus makes guitar, vocals, and synths sound thicker and more immersive, while flanging is more "dramatic" and is usually used to create unique sound textures.
A Note on the Third "Sibling": The Phaser
Since we’re talking about modulation effects, here’s another one we should at least mention: the phaser.
Unlike flanger and chorus, which play with the delayed signal, The phaser effect works by copying the original sound and shifting it between in-phase and out-of-phase.
In short, when you make a copy of your original sounds and play them at the same time, the two sounds are in phase, meaning they match perfectly. But if you flip one of those signals upside down, they are now out of phase, which makes the sound waves cancel each other out.
Unlike chorus and flanger effects, which use delays, a phaser splits the waveform into different parts and makes it slide back and forth underneath the clean signal. It uses all-pass filters to create this particular phase shift movement.
As a result, phasing creates sweeping gaps in the sound frequencies that feel smooth and engaging. Listen to Pink Floyd's " Shine On You Crazy Diamond " to get an idea.
Creative Tips: Using Modulation Effects
When you're working with different modulation effects, whether it's a delay pedal, a software plugin, or hardware units, there are some easy ways to enhance your music. Here are a few tips to get you started:
Be subtle (at least at the beginning)
A little bit of modulation can go a long way. For instance, adding a slight chorus effect to a lead guitar or vocal track can enrich the sound without taking attention away from the main melody. Start with gentle settings and gradually increase the effect until it fits perfectly with all other instruments.
Use Modulation to Add Movement to a Repetitive Riff
If long and sustained chords feel lifeless, you can use a chorus or flanger effect to create a more dynamic sound. Flanging can add a swirling texture to your riff, transforming static sounds into something more vibrant.
Use Flanging to Personalize Your Sound Signature
Flanging is great for making dramatic shifts in your music. It works particularly well during transitions or breakdowns because it grabs the attention more than most effects. Shorter delay times on the flanger can produce powerful moments that stand out in your song.
Combine Effects
Try to layer different effects together. For example, using a delay pedal alongside a flanger can create unique, evolving sounds. Mixing a phaser with a chorus can also bring to life lush and rich tones that will make your music more immersive.
Try Effects on Other Instruments
Modulation effects aren't just for guitars! They can also enhance other instruments. Aside from guitars and synths, you can add a flanger to a snare drum to give it an 80s vibe, or use chorus on bass to create a spacey and wide sound.
Play with Pitch and Timing
The magic of these effects comes from adjusting one sound against another. Using pitch modulation in a chorus can give a dreamy feel, and tweaking the timing in a flanger can create strong rhythmic pulses that catch the listener's ear. Explore the potential of your pedals and learn how to blend their sounds to perfection!
The Most Popular Chorus and Flanger Pedals
Here’s the list of what I believe are the best chorus and flanger pedals you can get.
Chorus Pedals
- Boss CE-2 Chorus : This classic chorus pedal is the one that inspired all the ones that followed. It has a warm and analog sound that makes it perfect for any genre, and I've seen it on the pedal board of most of the guitarists I've played with in my life.
- Electro-Harmonix Small Clone : Another legendary effect that’s been around for decades, the Small Clone is relatively inexpensive, but has nothing to envy to more blazoned chorus pedals. Kurt Cobain’s pedalboard included a Small Clone, distortion, and little else!
- MXR M234 Analog Chorus : A reliable Analog Chorus with a great range of effects, rate control and tone-shaping options.
Flanger Pedals
- Electro-Harmonix Electric Mistress Flanger/Filter Matrix : 1976’s Electric Mistress Filter Matrix is an absolute classic for flanging enthusiasts. The lush and otherworldly tones feel natural and enriching whether you strum chords or play powerful solos.
- Boss BF-1 Flanger : BOSS knows a thing or two about guitar pedals, and the BF-1 is an iconic effect that offers a plethora of modulation options, giving guitarists a wide sonic palette to work with.
- Ibanez FL-305 Flanger : A great old-school flanger with an exceptional modulation sound. The lush sound is perfect for strumming chords and creating psychedelic soundscapes.
Final Thoughts
I hope this guide helped clarify the doubts on these two great effects! Knowing their history, how they'd been used and by whom, and their unique sound characteristics, should open up new sonic opportunities for you and your artistry.
I want to conclude this article with a few notes on how to adjust the parameters of your modulation effect.
With a chorus effect, start by adjusting the Rate for the speed of pitch changes: use a slow rate for a smoother sound and a faster one for more energy, but be aware that the sound can spiral out of control easily.
The Depth controls the amount of pitch shift, with moderate levels sounding natural and the higher ones creating a thicker tone. Last but not least, the Mix control blends the effect with your original sound; lower settings add shimmer, while higher ones create intensity.
For flanger effects, adjust the Rate for modulation speed, and use Feedback to control how much altered sound loops back in. The Manual setting adjusts delay time, changing the sharpness and spaciousness of the output.
Have fun!
