Flanger Pedal: A Complete Guide

A flanger pedal produces a sweeping, metallic, jet-like effect by mixing a guitar signal with a slightly delayed copy of itself and modulating the delay time continuously. The result is a distinctive comb filtering effect — a series of notches that sweep up and down the frequency spectrum, producing the characteristic whooshing sound associated with classic rock and psychedelic recordings from the late 1960s onwards. Understanding how it works helps you use it musically rather than as a novelty.

How Flanging Works

The effect is produced by splitting the signal into two paths, delaying one by a few milliseconds, and mixing them back together. When the delayed and original signals combine, certain frequencies cancel out and others reinforce, creating a comb filter effect. By modulating the delay time slowly with a low-frequency oscillator, the comb filter sweeps through the frequency range, producing the whoosh. The rate control sets how fast the sweep moves; the depth control sets how pronounced the effect is.

Key Controls

Most flanger pedal designs share the same core controls: rate (speed of the sweep), depth (how dramatic the notch effect is), feedback (how much of the output is fed back into the input, increasing the metallic resonance) and manual (sets the centre point of the sweep). Higher feedback values produce the characteristic jet-plane or metallic flanger sound. Lower feedback settings give a subtle, chorus-adjacent effect. The manual control can create a static flanging effect when the rate is set to zero.

Musical Applications

Flanging is effective on rhythm guitar for adding movement to chord patterns, on clean arpeggios for a shimmering quality and on lead guitar for tonal colour. It is most commonly associated with heavy metal, classic rock and funk. Eddie Van Halen and Andy Summers are well-known for using a flanger pedal as a central part of their tonal identity. Bass players also use flanging for specific textural effects, and it works on keyboards and synthesisers as well as guitar.

Flanging vs Chorus vs Phaser

Flanging, chorus and phasing all use similar modulation principles but produce distinctly different results. Chorus uses slightly longer delay times and creates a thick, doubled sound without the metallic comb filtering. Phasing uses phase shifting rather than delay, producing a smoother, more subtle sweep. Flanging uses the shortest delay times and creates the most dramatic comb filtering effect of the three. All three are worth understanding in context — a flanger pedal is not simply an extreme version of chorus, and the effects are not interchangeable.

For advice on choosing the right model, see the buyer's guide. For getting started, see the beginner's guide.

Frequently Asked Questions