Let’s start with the obvious: the electric guitar is not just a loud acoustic guitar. The electric guitar is a three-part instrument comprised of the guitar itself, effects pedals, and the amplifier. Each of these contributes to the sound produced, and the possibilities encompass an enormous sonic range. Like any acoustic instrument, each electric guitar has its own soul that depends on the wood of its body, neck, and fretboard. Unlike an acoustic instrument, its tone is transformed into an electronic signal that can be altered downstream by the assortment of devices it encounters on its way to the speakers and shake up the air.
This article is geared toward composers who would like an overview of some of the electric guitar’s sonic possibilities and how to achieve them. While many of the sounds described here can be specified in a score, others are mentioned just to present some of what goes into the production of the electric guitar’s sound so the composer can get a broader picture of the technology behind the art.
In every guitarist’s world you are likely to find some wonderful and very personal idiosyncrasies: a homemade pedal, a unique playing technique, a rare amplifier, or a strange looking guitar salvaged from a flea market that sounds like nothing else on this or any other planet. So don’t rely on the limited and simplified list presented in this article. I encourage you to meet with the guitarist for whom you are writing and get inside the very personal approach to gear, technique, and style that he or she has developed. Then it is up to you how much you want to compose your piece toward that player’s personal approach versus composing for a wider and more general world of players.
Things electric guitarists do with their hands, part 1: Electronics on the guitar
Acoustic guitars have resonant bodies that amplify the sound of the strings mechanically. Electric guitars use “electronic pickups” to translate the energy of the vibrating string into an electric signal which is then amplified. Pickups are electromagnets fixed onto the body of the guitar and positioned under the strings. The vibration of the metal strings disturbs the magnetic field around the pickups on the guitar, which modulates an electric signal. That signal is ultimately responsible for what you hear. The signal can be colored a number of ways before it even leaves the guitar.
You probably know that when a string is struck, the center of the string will vibrate most with the fundamental frequency. The second overtone will vibrate most at 1/4 and 3/4 of the string’s distance. These locations of an overtone’s maximal vibration are called “antinodes”.
An electric guitar can have one or more pickups on it. The placement of the pickup will affect the mix of overtones it “hears”. A pickup located near the bridge has a bright sound that is rich in high overtones, with less of the lower overtones since it is so far away from the antinodes of these lower overtones. By contrast, the pickup near the neck has a richer warmer sound.
Guitars with more than one pickup might have a simple switch that selects one, the other, or both. More complex switching systems exist as well, where the signal phase between pickups can be specified. Pickups that are out of phase result in a very bright sparkling tone.
Pickups also have very unique sonic characteristics depending on their design. Single coil pickups found on the Fender Stratocaster for example have a very bright, clear, and penetrating sound. Humbucking pickups, like those found on a Gibson Les Paul for example, have a warmer, thicker sound. If you have a specific tone in mind, you should discuss the possibilities with your performer.
There are many ways of controlling an electric guitar’s volume, including the general level of the amplifier, settings on pedals, and of course, how hard the strings are struck. Leave it up to the performer how to manage the dynamics written into your score in whatever way is personally appropriate for that player. That said, the volume knob on an electric guitar controls the amplitude of the signal leaving the guitar. Some guitars have one volume knob per pickup, allowing for customized mixing of the signals sent by the pickups, while others have a single master volume. Interestingly, reducing the volume on the guitar sometimes does more than reduce the loudness level. It can influence the guitar’s tone in subtle ways.
The tone knob controls the brightness of the guitar signal like the treble knob on a stereo. Some guitars have a separate tone knob for each pickup, while others have one master knob. You can roll the tone knob down and get a very mellow, round sound, or max it out for a very bright sound. Knob positions are numbered 1-10. Don’t let me deter you from writing a piece where tone knob positions are specified and used as a varying compositional element. Just know that the effect will vary dramatically from guitar to guitar, and that the response is non-linear (so 5 is not “half” as bright as 10, for example). If it matters, most composers will probably be happy with the result by just specifying “mellow tone” or “bright tone” in a score.
Things guitarists can do with their feet: stompboxes and pedals
There is an enormous consumer-driven universe of pedals and stompboxes which alter the signal after it leaves the guitar and before it hits the amp. Pedals offer smoothly changing control over some sonic effect as the foot presses the pedal forward. Stompboxes do not have this continuous foot control, and instead have a switch that simply turns an effect on or off.
A reasonably standard arsenal of effects might include a wahwah pedal, volume pedal, and stompboxes that provide distortion, compression, and echo.
A wahwah pedal filters the frequency spectrum of a guitar’s tone, typically sweeping from a mellow tone in the pedal’s heel position to a bright tone in the toe position. Sweeping from heel to toe makes the “wah” sound that gives the pedal its name. Various flavors of wahwah pedals sweep through different ranges of the frequency spectrum and will specify to differing degrees the narrowness of the frequency band they allow to pass through. Wahwah pedals don’t have to be moved to put their signature sound on the music. Some guitarists will leave the pedal in a particular position to achieve a unique tone.
Like the volume knob on the guitar, the volume pedal controls how much signal passes downstream. In the heel position, it may eliminate all or most of the signal. In the toe position it will pass all of the signal through. Besides using it as a hand-freeing way to adjust the dynamics of the guitar, actively sweeping the pedal can achieve rich effects. For example, a guitarist can remove the attack from the sound by plucking while in the heel position and bringing up the volume immediately afterwards. Wilder foot moves on a volume pedal open up more possibilities. A composition that showed cresc/decresc indications with “use volume pedal” written nearby would send a clear message to any electric guitarist.
Fuzz and overdrive
Electric guitar distortion comes in many flavors, including “fuzz” which severely colors the frequency spectrum with non-harmonic overtones, and “overdrive” which enriches the spectrum with harmonic overtones, making it sound warm and full. The effects range from a face-melting scream to a clear, sustained, liquidy tone. Playing chords with lots of non-harmonic fuzz will sound awesome, but don’t get too picky about discerning the nuances of intervallic relationships if you do this. Note that distortion can also expand the frequency spectrum of the guitar and invade the spectra of other instruments, possibly masking them in some passages. These may be effects you desire, so let your ears decide as you ask your guitarist to dial through some possibilities. If you have an image in your head of the sound you want, it’s best to describe it in your score rather than direct the guitarist toward a particular solution. For example, seeing “sustained, singing” in a score would direct me toward my overdrive box while “harsh, abrasive, dark tone” might make me reach for a fuzzbox.
A compressor squashes the loudness contour of the guitar signal, reducing the hottest amplitude peaks and boosting the quietest. The effect is a sustained tone: as a guitar signal naturally dies out, the compressor boosts its level. This can be used to sustain the tone of a guitar much longer than it would naturally sound. If I read “clean sustain” in a score, I’d go for my compressor. Note that the compressor will boost everything that is quiet, including finger noise.
An echo unit records its input signal and can play it back in a number of ways. Short time delays between echoes create a timbral thickening, while longer delays will be heard rhythmically. Echo units have feedback knobs, which determine how many repeats you’ll hear before the echo dies out. So, just writing “with echo” in a score would be very ambiguous. You really would want to clarify its characteristics. Directions such as “single slap echo” or “with echo, delay timed to triplet, long decay” would get your message across clearly.
Things electric guitarists do with their hands, Part 2: mechanics
The whammy bar, also called the tremolo bar, is a lever attached to the bridge of some electric guitars. Depressing the bar toward the body of the guitar tilts the bridge toward the strings, loosening tension on the strings, and causing their pitch to drop. Pulling the bar away from the body of the guitar increases tension on the strings and causes their pitch to rise. Musical results like the “dives” heard in heavy metal can be achieved with the whammy bar. Subtler colorations like gentle vibrato are possible too. Whammy bars vary in the range of tensioning they are capable of altering. Some can be depressed so far that the strings go completely floppy, while others are considerably more restricted. If you are composing specifically for whammy bar, meet with your guitarist and find out what the limits are. Otherwise, your score can specify bends and pulls as gestural directions, but don’t expect the range of the bends to be uniform from guitar to guitar.
This is a plectrum effect, where the guitarist’s thumb strikes the string immediately after the plectrum strikes it, canceling lower harmonics and resulting in the highest overtones being heard. Sounds great quiet, sounds great loud. I would not write the harmonically induced pitch on the score, as these whistles are a bit unpredictable and vary according to where on the string they are plucked.
Two handed tapping is a technique where the guitarist’s right hand hammers down on a string, pushing it down to the fretboard so it sounds its pitch, then releases the string with a little pull, causing it to sound the pitch where the left hand has stopped the string. Tapping can be used to achieve complex high-speed rhythmic patterns, as well as ornamenting a melody with smooth intervallic leaps that would be impractical using a plectrum. If you are going to compose a tapping passage, you really need a map of the strings and fretboard in your head. Make sure that what you are writing is physically possible.
Scraping a pick along a string sounds noisy, aggressive, and is a real thrill. If you want a guitarist to scrape a pick along a string, your score might indicate something like, oh, I dunno, “scrape pick along string”.
Things electric guitarists can attach, touch, swing, and bang
Invented by Greg Heet, the E-Bow (Electronic Bow) is a unique device that is held over string, and without actually touching it, causes it to vibrate indefinitely. The E-Bow gives any steel string infinite sustain. Note that it takes a little moment to bring the string up to speed, so while fast passages on a single string are manageable, melodies that skip strings need to be slower to accommodate the physics of the device. When the ebow gets near the pickup, the tone gets extremely harsh, which is an effect you can play with. More at www.ebow.com.
The electric guitar can radically change its sound when its strings are prepared with objects attached directly to the string, placed above them, below them, or braided in between. Alligator clips attached to a string transforms the overtone series of the string into an enharmonic bell-like timbre. Plucking the string on one side or the other of the attached clip results in different sounds.
Braid a thin dowel between three or fours strings. Striking the dowel will cause it to seesaw and rhythmically sound the strings as it does so. For this it is most practical to lay the guitar flat on a table or lap. Loosen the strings and insert a thick dowel under all six strings for a koto-like effect.
You might also consider striking the strings with chopsticks (i.e. lightweight drum sticks). You can control the ringing of the strings by stuffing some piano felt under them.
Piping a recorded sound source through an earphone placed near a guitar pickup will transmit that signal through the guitar. Swinging the earphone over the pickup in a pendular fashion will bring the sound in periodically, depending on the length of cable from which it is swinging.
One last word on notation
Many of these effects are best described in your score using simple language. Avoid making up new symbols when an instruction such as “wiggle whammy bar spastically throughout passage” is clearer than a newly invented wiggly arrow. Note however that there is a set of symbols that is generally available to notate common effects. Guitar Player magazine has a good source online in PDF format at: www.guitarplayer.com/Notation.pdf.
Thanks to the friends and colleagues from whom I’ve culled some of the ideas presented here: Chris Murphy, Bill Horvitz, Rene Lussier, Fred Frith, Mark Stewart, and Keith Rowe. Brilliant guitarists all…my love and respect.
Nick Didkovsky has never owned an acoustic guitar. His recent CD “BONE, Uses Wrist Grab” (Cuneiform Rune 178) with Hugh Hopper and John Roulat serves up a variety of slawed, beaten, and fried electric guitars. Nick can be investigated further at www.doctornerve.org.