What Are Octave & Pitch-Shift Effects?
Your first question might just be ‘what are octave and pitch-shift effects?’ – and pitch might just be the key word here. To put it simply, both types of effect adjust the pitch of the sound that goes into them. This means they take a note (or notes) that’s detected and change it to a different note.
The Octave Effect
In musical theory terms, an octave is the distance (also known musically as an ‘interval’) between two of the same note. You may already know that musical notes repeat themselves in a seemingly endless cycle. So if you start with a C note and ascend 12 notes (12 frets on a guitar), you end up on a higher C. See the diagram below:
So the idea of an octave effect is that it takes the note that it detects, and shifts it by exactly 12 notes either up or down. This means that if you play a C note through an octave pedal, you’ll still hear a C, but it’ll be either an octave higher or lower than you played it.
Some octave effects can also shift by more than 1 octave. Instead of shifting by just 12 notes (1 octave), they can shift by 24 notes (2 octaves), or even 36 notes (3 octaves), allowing you to create really unique sounds. Some pedals even allow you to layer multiple octaves, creating an organ-like effect.
Most octave effects allow you to either blend the affected note with your original tone OR remove your original tone from the mix entirely. You can fatten up riffs by adding lower octaves to the mix, add extra sizzle to your leads with higher octaves, or drop your sound down by an octave or two and pretend you’re playing a bass...and much, much more!
The Pitch-Shift Effect
The idea behind a pitch shift effect is that it doesn’t just shift by octaves, it can shift by any chosen interval. One note, 5 notes, you can choose. And as with octave effects, you often have the option to either blend the effect with your signal, or remove your signal completely, opening up a world of tonal opportunities. You can mimic different tunings, reach higher or lower notes than your guitar allows, or create abstract textures that sound less and less like guitar the further you go!
…this brings us onto harmonisers! ‘Harmony’ is defined by the Cambridge English Dictionary as “a pleasant musical sound made by different notes being played or sung at the same time”. With harmonisers, you choose the musical key that you’re playing in, you choose your interval, and the pedal does the rest. Every note you play will have a perfect harmony added on top! This is more commonly used for vocalists who want a rich, layered sound, but when applied to guitar it can make for some really interesting effects!
The Nitty Gritty
Now that we’ve covered the basics, let’s take a closer look at the details. There’s a wealth of octave & pitch-shift pedals and effects available on the market today, and each one works slightly differently to the next. This is determined by a number of variables that are worth considering – see below!
In order for your octave or pitch-shift pedal to work its magic, it needs to be able to accurately detect your signal. This is called ‘tracking’, and different effects track your signal in different ways.
You can have digital or analogue tracking – older or vintage-themed octave effects often use analogue, which adjusts frequency, amplitude and filtering of your signal. This means that the result varies depending on use, and often sounds raw and fuzzy and with a subtle ‘warbling’ quality. This sound was famously pioneered by Roger Mayer, who produced the ‘Octavia’ pedal, heard on some of Hendrix’s most iconic recordings.
Digital tracking is found on a lot of modern octave effects, and is used on all pitch-shift / harmoniser pedals. It’s more accurate, and is therefore more flexible and applicable to a broad range of sounds. The ‘warbling’ sound of analogue pedals is created when the pedal has trouble tracking the signal; this problem is far less common with digital pedals.
Further to this, tracking can also be monophonic or polyphonic. Polyphonic tracking means that pretty much anything you play can be detected and shifted accurately, including chords. Analogue effects are almost always monophonic, which is often why they have trouble tracking; the minute they detect an overtone, a bum note, or an accidental open string, they get confused! Digital effects can be either mono/polyphonic – it depends on the one you go for.
The order of pedals in your chain has a massive effect on your tone. Octave and pitch effects are most commonly placed at the front of your chain (after tuners & volume pedals), with a clean signal going into it. This ensures the cleanest input signal, which means the note can be easily tracked. This can be changed to achieve unusual sounds, for example placing one after a fuzz pedal to create an abrasive, warped sound.
Some octave & pitch effects can be tweaked and manipulated in real-time by using an expression pedal. You can get pedals that allow you to attach a generic expression pedal, or some that have one built-in. This adds a whole new dimension to your sound, allowing you to adjust the blend of the effect, or even to glide to a different note / create weird divebomb effects.
Each octave or pitch effect pedal will have its own character. This can be determined by tracking, circuitry, aesthetics and so on – but some offer extra controls that allow you to tweak your tone that little bit extra.
- Gain / OD – Some allow you to dial in a little bit of extra gain or distortion, so your pitch effect can double up as a kind of boost! This is particularly suited to octave-up effects, giving your lead tone some extra sparkle.
- Attack – The attack can also be adjusted on some pitch pedals. Combining a softened attack with pitch/octave effects gives you a weird, synth-like sound (see video example 4). Use for extra funky solos or combine with delay and reverb for incredible ambient textures!
- Detune – Some pitch pedals also allow types of detuning, creating a chorus-like effect. Chorus, after all, is achieved by manipulating pitch, so the two tie together quite nicely.
- Filter – Give your octave or pitch effect a little more (or less) resonance. If you want to achieve a dirty, lo-fi sound, some pedals allow you to use a filter to round off certain frequencies. The alternative is to give your tone some added sheen by boosting those same frequencies.
- Presets – As with a lot of effect types, some pitch pedals allow you to save presets. This is extremely handy if you take an all-of-the-above approach, but can’t afford to fiddle with your board in the middle of a track!
These pedals are just a small selection of our favourites - let's take a closer look:
- Boss OC-3 – hailed as the world’s first polyphonic octave pedal, the OC-3 allows you to add either one or two octaves below your signal. It builds on the classic analogue OC-2 design, a workhorse pedal favoured by countless guitarists for its woolly octave tone. The OC-3 has built-in distortion and significantly improved digital tracking.
- Mooer Pitch Box – this super straightforward micro-pedal combines digital tracking with a simple one-knob and one-switch interface. You have 15 different intervals to choose from, up to two octaves above or below, plus a neat built-in ‘detune’ feature; this creates a cool wobbly chorus effect with microscopic tweaking the pitch of the input signal.
- Digitech Whammy DT – the Digitech Whammy combines pitch shifting, octave effects and an expression pedal for maximum versatility. Offering two octaves above, two octaves below and a wealth of intervals in between, the DT also features a drop-tune effect, a detune (chorus) effect and a momentary switch – this means you can stomp the pedal for particular points in a riff. This crazy red box has it all!
- Electro-Harmonix POG-2 – short for Polyphonic Octave Generator, this incredible red box does what it says on the tin. Two octaves above and below can be faded to your preferable level, then blended with the dry signal, faded attack, a Low-Pass filter, detune and the ‘Q’ switch for even more snap and crackle! You also have 8 user presets at your disposal, so you can easily switch between heavy sub-riffage and sparkling harmonised leads!
Here are a couple of great examples of octave / pitch effects in action. We’ve also included a few pedal recommendations to help you nail that tone:
The White Stripes – ‘Seven Nation Army’ – Arguably one of the most iconic riffs of the 21st Century so far. Jack White shifted his guitar down an octave to mimic a bass tone. This allowed him to recreate the track live without drafting in a bass player. White is known for using a number of digital octave effects that can be heard on all of the White Stripes’ releases. Recommended gear: Boss OC-3 Super Octave
Rage Against /the Machine – ‘Know your enemy’ – Tom Morello is known for his creative use of pitch effects. For the intro to this track, he pitch-shifts up by 7 notes and blends it evenly with his dry signal. This creates an abstract, almost robotic tone that is instantly recognisable. He applies the same effect to the solo at 3:14 – madness ensues. Recommended gear: Mooer Pitch Box Harmony Pedal
Snarky Puppy – ‘The Clearing’ – Skip to 8:08 to hear Snarky Puppy’s guitarist Mark Lettieri use a layered octave effect with a softened attack. His tone adopts a synth-like persona that could be easily mistaken for a Moog. Recommended gear: Electro-Harmonix POG 2
Steve Vai – ‘Touching Tongues’ – Skip to 1:12 and you’ll hear Vai combining an upper octave shift with an expression pedal, allowing him to control the application of the effect. This allows him to create an entirely new melody, making huge jumps in pitch without having to run up and down the fretboard…not that he couldn’t do that anyway! Recommended gear: Digitech Whammy DT
Hopefully you’re now feeling a little more informed. You now know what pitch-based effects are, how they work, how they differ and how they can be used.
You may also have some questions to ask yourself: how often will you be using this effect? Will you be using it for lead or rhythm? Do you want your guitar to still sound like a guitar? Will you need multiple effects in one unit? Consider these questions carefully, refer to this information, and you’ll find the pedal that’s right for you in no time!
P.S. Have you checked out our other buyer's guides? You might just find something you like!