# AI Wiki - Music - Guitar Effects ## Overview An effect changes the guitar signal on its way to the amp: it makes it louder or more even, filters it, distorts it, moves it in time or pitch, or repeats it. Effects come as **pedals** (stompboxes), as **multi-effects** units, built into **modeling amps**, or as software plugins. They are part of a style's vocabulary (the wah in funk, the delay in dub, the fuzz in 1960s [[AI Wiki - Music - Rock Music|rock]]), but they amplify your playing, good and bad. This article assumes the amp basics from [[AI Wiki - Music - Guitar Amps and Tone]]. Effects are mainly an [[AI Wiki - Music - Electric Guitar]] matter; acoustic players use a few (reverb, chorus, a tuner, an acoustic preamp) through an [[AI Wiki - Music - Electro-Acoustic Guitar]]. ## The categories | Category | What it does | Common pedals | Typical use | | --- | --- | --- | --- | | **Dynamics** | Changes loudness | Compressor (MXR Dyna Comp, Boss CS-3), noise gate (Boss NS-2), volume pedal, clean boost | Even clean funk and country picking, sustain, silence between high-gain chugs, swells | | **Filter** | Boosts or cuts frequency bands | Wah (Dunlop Cry Baby, Vox), envelope filter / auto-wah (Mu-Tron III), EQ (Boss GE-7) | Funk rhythm, vocal-like leads, tone correction | | **Drive** | Clips the signal | Overdrive (Ibanez Tube Screamer), distortion (Boss DS-1, Pro Co RAT), fuzz (Fuzz Face, Big Muff) | Blues, rock, metal; boosting an already driven amp | | **Modulation** | Varies the signal over time | Chorus (Boss CE-1), flanger, phaser (MXR Phase 90), tremolo, vibrato, rotary | Shimmer, movement, swirl, choppy pulse | | **Pitch** | Adds or shifts notes | Octaver, harmonizer, DigiTech Whammy (1989) | Bass-like octaves, harmony lines, dive effects | | **Time-based** | Repeats the signal | Delay (Boss DD-3, MXR Carbon Copy, tape echo like the Roland RE-201), reverb, looper | Space, echo rhythms, ambience, practice loops | ### Dynamics A **compressor** turns loud notes down and quiet ones up, so a part sounds even and notes sustain longer. Used lightly, it's the secret of clean funk scratching and country [[AI Wiki - Music - Hybrid Picking|chicken picking]]; used heavily, it squashes the attack and hides your dynamics. A **noise gate** cuts the signal below a threshold: essential for tight high-gain rhythm (see [[AI Wiki - Music - Metal Rhythm Guitar Techniques]]) but no substitute for muting with your hands ([[AI Wiki - Music - Muting Techniques]]). A **volume pedal** gives violin-like swells (fade the note in after picking it). ### Filter A **wah** sweeps a resonant peak through the frequency range as you rock the pedal: heel = dark, toe = bright. Rocked in time with sixteenth-note scratching, it's the "wakka-wakka" of 1970s soul and [[AI Wiki - Music - Funk Music|funk]] ("Theme from Shaft"); parked half-open, it's a nasal fixed-filter lead sound. An **envelope filter** (auto-wah) moves the filter with your picking strength instead of your foot; the Mu-Tron III is the classic, heard on Stevie Wonder's clavinet in "Higher Ground". ### Drive All three clip the waveform; they differ in how hard and how abruptly: - **Overdrive**: soft clipping that imitates a tube amp starting to break up; responds to pick attack and to the guitar's volume knob. The Tube Screamer is also used as a *boost* into an already driven amp, which tightens the bass and adds mids for solos. - **Distortion**: harder, more compressed and saturated, less dependent on how you play. - **Fuzz**: extreme clipping toward a square wave; buzzy and thick. The Maestro FZ-1 (1962) became a hit after Keith Richards used it on "(I Can't Get No) Satisfaction" (1965). Pick one drive sound you like and learn to control it with your hands and the guitar's volume knob before stacking pedals. ### Modulation These copy the signal and vary a copy, or the volume, with a slow oscillator (rate and depth knobs). **Chorus** detunes a short delayed copy slightly, for a shimmering, doubled sound (1980s clean tones, Nirvana's "Come As You Are"); the Boss CE-1 (1976) took the chorus from Roland's JC-120 amp into a pedal. **Flanger** is a stronger, jet-plane sweep; **phaser** a softer, swirling one. **Tremolo** pulses the volume (built into many old Fender amps, a staple of surf and swampy [[AI Wiki - Music - Blues Music|blues]]); **vibrato** wobbles the pitch. ### Time-based - **Delay** repeats what you play. Three knobs: **time** (gap between repeats), **feedback** (number of repeats), **mix** (level of the repeats). A **slapback** is a single short repeat (roughly 80-150 ms), the sound of 1950s rockabilly and much [[AI Wiki - Music - Country Music|country]]. Long, swelling repeats with high feedback are the core of [[AI Wiki - Music - Dub Music|dub]]. - **Reverb** imitates a space: spring (the drip of a Fender amp tank, surf and [[AI Wiki - Music - Reggae Music|reggae]]), plate, room, hall. A little adds life; a lot pushes the guitar to the back of the mix. - A **looper** records a phrase and plays it back: great for practising solos over your own rhythm part. ## Delay in time: the dotted eighth Delay time is a rhythm. A quarter note lasts **60,000 / BPM** milliseconds: 500 ms at 120 BPM. An eighth note is half of that (250 ms); a **dotted eighth** is three quarters (375 ms at 120 BPM, 360 ms at 125). Most delays have a **tap tempo** button: tap quarter notes and pick the subdivision. Set to a dotted eighth with one repeat and a mix about as loud as your playing, the delay turns a line of steady eighth notes into a stream of sixteenths: the echo of each note lands in the gap between the next two. That's the Edge's sound in U2's "Where the Streets Have No Name". It only works if your eighth notes are dead in time (see [[AI Wiki - Music - Rhythm and Time Signatures]] and [[AI Wiki - Music - Metronome and Speed Building]]). ```chords {title: Dotted-eighth delay} {tempo: 120} {comment: Delay 375 ms, one repeat, mix about equal to the dry sound. Play only the eighth notes; capitals = what you play, lower case = the echo.} {start_of_tab} e|2-----------5-----------2-----------5-----------| B|------3-----------3-----------3-----------3-----| G|------------------------------------------------| D|------------------------------------------------| A|------------------------------------------------| E|------------------------------------------------| 1 e & a 2 e & a 3 e & a 4 e & a F# d D f# A d D a F# d D f# A d D a {end_of_tab} ``` The played notes (F#, D, A, D: a D major [[AI Wiki - Music - Arpeggios|arpeggio]] on the top two strings) fall on the beats and "&"s; their echoes fill every "e" and "a". Light palm muting keeps the notes short so the echoes are heard. ## Signal chain order There are no fixed rules (Fender's own guide says so), but this order is the usual starting point, and the reasons behind it are worth knowing: 1. **Tuner** first, so it gets the cleanest signal and can mute everything. 2. **Filter (wah)** and **compressor**: they shape the raw guitar signal. Vintage-style fuzzes often go first of all, because they react to the guitar's pickups directly. 3. **Drive** (overdrive, distortion, fuzz): a drive pedal amplifies everything before it, so noisy or time-based effects go after it. 4. **Modulation** (chorus, phaser, flanger, tremolo). Phasers are also often placed before drive for a different, more aggressive sweep. 5. **Delay**, then **reverb** last: delays placed before drive get their repeats distorted into mush; reverb sounds most natural when nothing changes it afterwards. 6. **Looper** at the end if it should capture the whole sound. A **noise gate** goes after the drives (or in the effects loop) to stop the hiss they add. ### The effects loop Many amps have an **effects loop** (send/return jacks) between the preamp and the power amp. If you get your distortion from the amp's preamp, put modulation, delay and reverb in the loop: they then come *after* the distortion, as in the order above. Drive, wah and compressor still go into the amp's front input. Multi-effects units can do both with the "four-cable method" (guitar to unit, unit to amp input, amp send to unit, unit to amp return). ## Which pedals first For a returning player, very few: 1. **A tuner** (clip-on or pedal). Not an effect, but the one item everyone needs. 2. **One drive** (an overdrive) if the amp's own crunch is weak. 3. **Delay or reverb**, if the amp lacks them. 4. Later, only if a style asks for it: **compressor** and **wah** for [[AI Wiki - Music - Funk Music|funk]], **noise gate** for [[AI Wiki - Music - Metal Music|metal]], **chorus** for clean 1980s sounds. A modeling amp or a multi-effects unit (Boss GT/ME series, Line 6 POD and Helix, Zoom, Headrush) gives all of these at once, with presets, an amp simulator and usually a USB recording interface, for the price of two or three pedals. The trade-offs: menu diving, and the temptation to scroll presets instead of practising. Individual pedals are simpler to tweak with your foot and easier to understand one at a time. Both are fine; the music matters more than the format. ## Using effects musically - **Practise dry first.** Delay, reverb and gain hide timing slips and sloppy muting; a clean sound reveals them (see [[AI Wiki - Music - Guitar Lead Techniques]]). - **Serve the song.** Turn effects on for a section (chorus for the bridge, delay for the solo) rather than leaving everything on. - **Set them in context.** Reverb and delay that sound lush alone wash out in a band mix; set the mix lower than feels right alone. Check against a backing track ([[AI Wiki - Music - Playing with Backing Tracks]]) or a recording ([[AI Wiki - Music - Recording Yourself]]). - **Lock time-based effects to the tempo.** Delays and tremolos set to the song's beat add groove; random times add clutter. - **Learn a style's effect vocabulary**: slapback for rockabilly and country, spring reverb and delay throws for reggae and dub, wah and compression for funk, a boosted overdrive for blues, a gated high-gain sound for metal, a glass slide with compression for [[AI Wiki - Music - Slide Guitar|slide]]. ## Common mistakes - **Too much of everything**: gain, reverb and delay mix at maximum. - **Delay before distortion** by accident, giving muddy, distorted repeats. - **Battery and power noise**: use an isolated power supply rather than daisy-chained cheap adapters. - **Long cable runs with only true-bypass pedals** can dull the treble; one buffered pedal or a buffer early in the chain fixes it. - **Effects as a crutch**: if a part only works with delay on, practise it dry until it works without. ## Key Points - Categories: dynamics, filter, drive, modulation, pitch, time-based. - Usual order: tuner, wah/compressor, drive, modulation, delay, reverb; no rule is absolute. - Delay before drive gets distorted; put time-based effects after drive or in the amp's effects loop. - Delay time is rhythm: quarter = 60,000 / BPM ms; dotted eighth = 3/4 of that (375 ms at 120 BPM). - Start with a tuner, one drive and a delay or reverb; a modeling amp or multi-effects covers the rest. - Practise dry; use effects to serve the song and the style. ## Open Questions - Which multi-effects or modeling unit fits a home-practice and recording setup best? - Which effects do the songs on Sébastien's learning list actually use (to recreate their sounds)? - How do analog pedals compare to modeled versions in blind listening tests? ## References - Wikipedia, "Effects unit": https://en.wikipedia.org/wiki/Effects_unit - Wikipedia, "Distortion (music)": https://en.wikipedia.org/wiki/Distortion_(music) - Wikipedia, "Guitar amplifier": https://en.wikipedia.org/wiki/Guitar_amplifier - Premier Guitar, "Electric Etudes: U2's the Edge" (dotted-eighth delay): https://www.premierguitar.com/electric-etudes-u2s-the-edge - Fender, "Mass Effects: How to Compose an Effective Effects Chain": https://www.fender.com/articles/tech-talk/mass-effects-how-to-compose-an-effective-effects-chain - Andertons, "Should I Use a Guitar Amp Effects Loop?": https://blog.andertons.co.uk/learn/should-i-use-a-guitar-amp-effects-loop - Thomann, "Pedalboard Basics: How to Set Up and Organize Your Effects Chain": https://www.thomann.de/blog/en/gear/order-connect-effect-pedals/ ## Related - [[AI Wiki - Music - Guitar Amps and Tone]] - [[AI Wiki - Music - Muting Techniques]] - [[AI Wiki - Music - Guitar Lead Techniques]] - [[AI Wiki - Music - Funk Music]] - [[AI Wiki - Music - Reggae Music]] - [[AI Wiki - Music - Dub Music]] - [[AI Wiki - Music - Country Music]] - [[AI Wiki - Music - Metal Music]] - [[AI Wiki - Music - Metal Rhythm Guitar Techniques]] - [[AI Wiki - Music - Slide Guitar]] - [[AI Wiki - Music - Rhythm and Time Signatures]] - [[AI Wiki - Music - Metronome and Speed Building]] - [[AI Wiki - Music - Playing with Backing Tracks]] - [[AI Wiki - Music - Recording Yourself]] - [[AI Wiki - Music - Home Recording Basics]] - [[AI Wiki - Music - Electric Guitar]] - [[AI Wiki - Music - Electro-Acoustic Guitar]] - [[AI Wiki - Music - Guitar Setup and Maintenance]] - [[AI Wiki - Music - Guitar Types Compared]] - [[AI Wiki - Music - Harmonics]] - [[AI Wiki - Music - Power Chords]]