Guitar Effects Pedals - An Introduction and Buying Guideasd

Effects pedals for the guitar have been around since the 1960s, when electric guitar based music and rock 'n' roll were on the rise. Roger Mayer, an engineer, is believed to have created the first guitar effects pedals, which were the "fuzz box" (today known as distortion or overdrive) and the "wah-wah" pedal. Mayer created pedals that were used by the likes of legendary rockers Jeff Beck, Jimi Hendrix, and Jimmy Page (for whom Mayer, his friend, reportedly created the first pedal in 1963 or 1964). Today, numerous effects are widely used by electric guitar players.
Effects pedals are used to give the guitarist more tonal colors or, that is, an expansion of timbre on his instrument's palette. It's possible to use an amplifier's settings to create these different tonal colors, too, but the amplifier is limited to what effects it can give, plus its settings would have to be changed only between songs, whereas guitar players frequently want to change tonality and color in the midst of playing a single song, and often many times over. Just as the invention of the electric guitar and the amplifier gave the guitar player a far more powerful voice and greater sustainability of notes, so the effects pedals gave him a far wider range of expressive options.
Today, even some acoustic guitar players and classical guitar players use effects pedals although the distortion and overdrive pedals used by electric guitar players aren't usually part of their tonal palette. Since the first pedals were created, other guitar effects called rack mounted effects have been invented. These are widely used, too, but they require a more sophisticated and time-consuming approach (not to mention considerably more money) than the simple pedals. Rack mounted effects are themselves triggered by pedals.
So, armed with their pedalboards and an array of effects, electric guitar players have only to "stomp" to activate their effects (hence the name stompbox) to instantly switch on or switch off an effect. The wah-wah pedal is a little different than the others, as we'll see below. For instance, the ubiquitous distortion tone of hard rock and metal guitar players can be instantly switched off and the guitar's "clean channel" allowed to be played, to give a different feel to different sections of a song. Another simple stomp, and the distorted tone comes roaring back.
Guitar players go through a great deal of effort to tweak the settings on their guitar, their amps, and their configuration of effects pedals to get their "just right" or signature sound. What are their basic effects pedal choices today?
1) Distortion/Overdrive. The most widely used guitar effect in the world. Of course, this one is often left on for most or all of a rock song. This is the famous (or infamous to many people) sound of heavy metal. Metal guitarists typically use a type of overdrive called distortion, which can distort their tone even more than standard overdrive pedals. Distortion works by adding in tons of overtones to the actual note played. Popular distortion & overdrive pedals included offerings from Fulltone (such as the OCD or Fulldrive), Boss (DS-1, BD-2), and Ibanez Tubescreamers and their host of clones. Distortion and overdrive pedals are without a doubt the most popular type of pedal, so it would be impossible to list them all.
2) Volume and "wah-wah" pedals. Hendrix probably did the most to pioneer the wah-wah pedal. Unlike other effects pedals, this pedal is used by way of keeping your foot on it and applying more or less pressure. A volume pedal, while operated in the same way as a wah pedal, allows a guitarist to rapidly sweep the volume of his instrument from full to completely silent. This is the pedal that is used to create an electric guitar's "violin sound", such as on the first part of Rush's "Xanadu." The wah pedal creates the "chugga-chugga" and "crying baby" sound (like Stevie Ray Vaughan's or Hendrix' intro and outro to "Voodoo Chile"). Popular wah pedals included the Dunlop Crybaby, the Vox Reissue Wah, the Teese Wizard Wah, and the Fulltone Clyde Wah. The Ernie Ball volume pedal is popular, as are models by Visual Sound and Boss.
3) Compression. Basically speaking the compressor pedal is used to make soft notes louder and loud notes softer. This is often used in conjunction with distortion/overdrive to help balance out the guitar player's sound and give him consistency. Popular compression pedals included the Keeley Compressor, the MXR Dyna-Comp, and the Boss CS-3.
4) Chorus. The chorus pedal is popular among guitar players who need or want to create a "spacious" sound. Like distortion, chorus adds overtones to the note played, but they are more widely spaced out and they are on a very slight delay, meaning they sound very, very slightly after the original note. Chorus and distortion can be used together to give a guitarist a gargantuan sound, or chorus can be used to make a clean channel sound feel richer and fuller. Popular chorus pedals include the Boss CE-3 and Visual Sound H20.
5) Flangers. Flangers are offshoots of the chorus pedal. With the flanger, the guitarist picks one note, but two of them sound; except, the second note sounds on a very, very slight delay. Flangers are used to create deep resonance in a guitar player's sound, but some guitarists insist that if you use a chorus you don't need a flanger. The Boss BF-3 is a popular flanger pedal, as is the Fulltone Choralflange.
6) Phasers. Another take-off of the chorus, the phaser pedal is used similarly to a flanger, but it gives a different sound because it doesn't harmonically relate the two notes. Instead, it takes the original notes and puts it "out of phase" as a second, additional note, meaning that it's mathematically shifted across the frequency spectrum. Phasers can give "other-world" effects or make distortion that much more mind-boggling. The MXR Phase 90 is a very popular phaser pedal, as are the Red Witch Deluxe Phaser and the Electro-Harmonix Small Stone Phase Shifter.
7) Delay. Delay pedals are used to give a very prominent echo-effect. They, too, operate like a flanger, except the delayed signal is substantially more delayed, perhaps even by a full second or two. Popular delay pedals include the Line 6 DL-4, the Boss DD-3 and the Visual Sound H20.
8) Pitch shifters. Also known as Harmonizers or Octave pedals. These produce overtones that are one, two, or three octaves above the original note, or they can be changed to produce harmonic notes at specified intervals. These can give the effect of the guitar player accompanying himself. The Boss PS-3 is a popular pitch shifter pedal, as is their OC3 Octave pedal.
9) Tremolo. This gives an effect like very rapidly turning the guitar's volume control up and down. It's not the same as "vibrato", which as an effect is typically created using the "whammy bar" on the guitar. Popular tremolo pedals include the Fulltone Supa Trem, the T-Rex Tremster, and the Boss TR-2.
10) Vibrato. This is usually accomplished with a "whammy bar" on the guitar itself, which was made famous by Hendrix and Ritchie Blackmore. However, there are pedals for this, too. This is used to give some very dynamic effects, from an exaggeration of a bent note to a squeal to a "dive bomber" effect. Rather than a very rapid change in volume, it produces a very rapid change in pitch. Popular vibe pedals include the Fulltone Mini-Deja Vibe and the Voodoo Lab Micro Vibe.