Difference between revisions of "Guitar Parts and Functions"

Revision as of 13:54, 30 June 2014

The guitar can be divided into two main parts: body and neck. The terms front/back/side/etc can get a little confusing. Typically the part that faces the audience and has the strings, pickups, bridge, and controls is the front or face; and the part that faces your body is the back. All other parts of the body are called the side. All directionality is usually along the neck-body, or more commonly neck-bridge, axis. For example, a pickup is often called the neck pickup or the bridge pickup, based on whether it is the one closer to the neck or to the bridge.

Frets are numbered starting furthest from the body. Thus, lower and higher in relation to one's position on the neck refer to the numbers associated with the frets. For example, the further your left hand is from the guitar's body, the lower you are on the fretboard.

Higher and lower can also be applied to strings, and this gets confusing. When looking at the fretboard from a playing position, the thicker strings will be closer to the player and appear below the thinner strings. Thus, visually they are lower. Also, they are lower in pitch. Thus, typically the "low" strings are the thickest and high strings the thinnest, which is consistent with the visual layout of the fretboard and tablature. However, strings are numbered from thinnest to thickest, so numerically, the thinnest strings are the "lowest". Typically, low/high refers to visual layout/pitch, not string number.

Body

The body contains the tailpiece/bridge, pickups, toggle switch, knobs, cutaways/horns, neck heel, strap pins.

Tailpiece or Bridge

The tailpiece/bridge is the part that connects the strings to the body. There are numerous types. The Stratocaster's tremolo bridge is one of the more famous. It features individual adjustable saddles and a whammy bar. Some bridges are coupled directly to the guitar body, which claim to increase tone and sustain. Some are only attached to a few points, allowing the bridge to "float".

Pickups

Pickups are typically bars that reside between the bridge and the neck; however, they technically refer to anything that converts the string resonance into electricity. Typical pickups are either single-coil or humbuckers. Humbuckers are usually wider than single-coils because they use two coils. One is reverse wound, which makes any interference being picked up cancel out. Humbuckers are also typically wired in serial, which gives them greater output but also greater impedance, which makes them a bit more nasal-sounding. Single coils are associated with shimmering clean tones while humbuckers are a staple of heavily distorted tones.

Additionally, there are piezo pickups that detect vibration without using magnetism, useful to get an acoustic-like sound. And there are hexaphonic pickups that analyze each string and are typically used to convert the strings' motion into MIDI data.

Pickup-Selector Switch

The toggle or pickup-selector switch is usually the only switch on the front of an electric guitar. This is used to select which pickup is active. This can be wired in different configurations, but usually a 3 pickup guitar will feature a 5-way selector with neck, neck + middle, middle, middle + bridge, bridge as you move it from pointing towards the neck to the bridge. A 2 pickup guitar usually features a 3-way selector with neck, neck + middle, bridge.

Knobs/Controls

There are usually 2-4 knobs on the front of a guitar, and they function as either volume or tone knobs. The knobs connect to potentiometers (audio tapers), which add or decrease resistance to certain circuit paths inside the guitar. A volume knob functions as expected, reducing potential electrical output. A tone knob filters higher pitched frequencies, which allows the player to adjust the "darkness" or "brightness" of the tone. If the guitar has 4 knobs, this typically indicates that each pickup has its own set of volume and tone controls.

Electronics Cavity

There is typically a large hollowed out section of the body between the pickups and the output jack that houses any additional electronics, such as the potentiometers for the knobs, the pickup selector switch, connecting wires, and if necessary a battery.

Cutaways and Horns

Cutaways are the areas around where the neck meets the body. On an acoustic guitar, there are typically no cut-aways, making it difficult to access the highest frets on the fretboard. On electric, this part of the body is typically "cut away", allowing the player's hand to more easily access those frets. Depending on the body shape, this may leave horns - parts of the body that extend away from the body and towards the neck that resemble horns on animals.

Neck Heel

The neck heel is simply the "pocket" cut into the body designed for the neck to fit into, where it is then usually bolted on. Some guitars are made mostly from a single piece of wood, where the neck runs through the body (neck-through design). In this case, there is technically no neck heel, although it may still be used to refer to the place where the neck and body meet.

Strap Pins

The strap pins are metal studs screwed into the body that allow a strap to be attached to the guitar. They are typically located on the front of the top horn and bridge side of the guitar, in line with the strings. On some body shapes, there is no front horn, and the pin is either where the horn would be, or it is on the back of the body by the neck heel.

Neck

The neck has the headstock, tuners, nut, fretboard, and fret markers.

Headstock

The headstock is the end of the neck where the strings attach to the tuners. Manufacturers often have a signature shape/design for their headstock.

Tuners

Tuners are the metal pieces in the headstock that secure the string ends and are used to tighten or loosen each string's tension, changing its pitch. Most modern guitars use machine heads: the tuner consists of two parts linked together with gears. The part that holds the string is called a peg' or post (formally it's a capstan). The part you turn is called the knob.

Some tuners are locking tuners - they feature an additional screw or other means to clamp the string inside the tuning peg. This makes initially tuning a new string easier and prevents strings from slipping or rewinding differently after a whammy bar dive.

Nut

The nut is the 0th fret - the last part of the fretboard before the headstock. It is basically a fret that is always fretted. However, it is usually not made of metal, but of a hard plastic or bone.

Some nuts are locking nuts, using hex bolts to clamp the strings inside the nut, so that tension between the tuners and nut remains firm even during a whammy bar dive. Without the locking nut on some guitars, a strong whammy bar dive can cause the strings to slack to the point where they become unwound around the tuning pegs. When the whammy bar is released, the string may wind differently or not at all around the tuning peg, causing the tuning to be off.

Fretboard, Frets, and Fret Markers

The fretboard is the front part of the neck with the shiny metal bars called frets. The frets are used to sound specific pitches within the chromatic scale, but also make performing pitch bends and vibrato easier. The fret markers are usually on the top side of the neck and often on the front of the fretboard as well. They indicate the 3rd, 5th, 7th, 9th, 12th, 15th, 17th, 19th, and 21st frets.

Fretboards are often made of a different type of wood than the neck of the guitar, making them easier to identify. It is glued to the front of the neck.

Strings

Strings - strings are numbered 1-6 (on a six-string guitar), with 1 being the thinnest and 6 being the thickest. Sometimes they are called by their open pitch in standard tuning (covered in Tuning and Harmonics). Ex. the 2nd string is also called the b string. Since there are two open e strings in standard tuning, they are called "high e string" or "low e string". High/Low refers to pitch, so "high e" is 1st string; "low e" is 6th string. Electric guitar strings are typically made from nickel-plated steel. A typical set of electric strings has 6 strings - 3 wound and 3 unwound. Wound strings have a straight "core" string with another string wound around it - this adds mass and lowers the string's resonant pitch while maintaining higher elasticity than simply using a single thicker solid string. Strings typically have one end with a metal or plastic "ball" ending with the other side being simply cut. The ball ending is used to hold the string in place in the guitar's tailpiece/bridge, while the cut end is placed through the tuner and wound tight.

Non-guitar Parts

This covers common parts that, while not absolutely essential to learning or playing guitar, are used very often.

Pick or Plectrum

The pick or plectrum is a small, flat, usually triangular piece of plastic (or other materials) used to excite the strings. They generally have a tip used to make contact with the strings. There are a large variety of picks; I recommend you follow the instructions in the Choosing a Pick section to determine what you are most comfortable with.

Tuner

Unlike the tuners attached to the guitar, a tuner is a device that detects and displays pitch used to tune all the strings to the desired pitch. Tuners typically use one of the following sensors to determine pitch: electrical, vibrational, or audial. Electrical tuners are connected to the guitar via an instrument cable, using the electrical signal generated by the pickups. Vibrational tuners clamp or stick onto the guitar and use the vibrations induced by the resonating string. Audial use a microphone to listen to the sound produced by the resonating string.

I like electrical best, but this only works if you have an electric or acoustic-electric guitar. For more info, see Tuning and Harmonics.

Cables

Professional audio typically makes use of analog cables with 1/4" diameter jacks. Cables are generally described by how many lines they hold or how much power they can carry, which generally describes what they are used for. The jacks on each end of a cable have to be compatible with the cable, but can have much wider variety.

Instrument - Designed to handle single low-level signals generated by sensors or transducers, such as guitar pickups. Typically connects the guitar to an amplifier or pedal and uses 1/4" male TS jacks.
Line-Level - Designed to handle medium-level signals generated or amplified by electronic equipment before power amplifiers. Typically connects pedals or effects units to each other and to an amplifier's front input or effects loop and uses 1/4" male TS jacks if mono, TRS if stereo.
Speaker or Power - Designed to handle high-level signals generated by power amplifiers. Connects power amplifiers to speakers. Uses 1/4" male TS jacks.
Balanced - A balanced cable uses 2 lines instead of 1 to send and recieve a mono signal, which reduces noise or other interference found in unbalanced cables. Note: a balanced cable may be used to carry a stereo signal instead of a single balanced signal, losing its noise-reduction properties.
XLR - Usually a line-level cable, but uses 3-prong XLR jacks. Typically used as a balanced cable, but is also capable of 2 independent signals, such as a stereo signal.
TRS - Same as XLR but uses a 1/4" jack with 3 connections - tip, ring, sleeve (hence, TRS). More commonly used as a stereo cable instead of a balanced mono cable.
Coax - Looks similar to a standard RCA A/V cable, but uses a different resistance. Used to connect digital devices using S/PDIF encoding.
Y-cable - uses a stereo jack on one end to connect to two mono jacks on the other end.

Amplifier

In essence, an amplifier simply amplifies a signal. A guitar amplifier typically does much more, however. In addition to bringing the signal up to a level capable of driving a speaker, it will filter or EQ the signal, distort, and/or compress it. How this is done is usually controllable using provided Bass, Mids, Treble, Presence, and Gain/Drive controls. Most amplifiers have their own distinct tone/response, particularly in regards to distortion. They may have additional features such as a noise gate, reverb, and an effects loop. Also, most modern amps feature multiple channels, often with their own indepedent controls, used to switch sounds instantaneously using a foot controller.

Pedals/Effects

A wide variety of digital and analog devices exist to process a guitar signal in some way. These typically appear in either a rack or pedal form factor. Pedals typically have one function and are engaged or disengaged by stepping on them (which led them to be called stomp boxes). Rack effects are generally more complex, tackling multiple types of effects simultaneously, and are controlled by MIDI.

Here's a list of common effects:

Compression/Limiting
Distortion/Overdrive/Boosting
EQ/Filtering
Modulation (Chorus, Phaser, Flanger, Tremelo)
Pitch-Shifting
Synth/Waveform Processing
Delay
Reverb
Noise Gate/Expander
Wah-wah
Volume control

Capo

A capo is a device that uses a spring or screw to clamp the strings against the fretboard at any particular fret desired, effectively acting like the nut. This simply raises the pitch of the strings when played without being fretted. It's useful to play in different keys, using the open position chord fingerings but with the root notes that fit the desired key. For example, if you know a song in C and want to play it in D, you would either have to learn how to play it using different chord fingerings or voicings, tune each guitar string up a whole step which takes time and may make the strings too tense to play, or simply put the capo on the 2nd fret.

Advanced Parts

Let's quickly discuss more advanced stuff. This will help you identify these parts, but we save adjusting them for a more advanced lesson.

Truss Rod

The neck has a truss rod under the fretboard, connected to the headstock and end of the neck by the neck heel. This is used to put tension on the neck to counter the tension of the strings, preventing the neck from becoming concave. The ideal neck is somewhere between perfectly flat and slightly concave, which allows each fret to sound with minimal as well as near-equal fret buzz across the entire fretboard.

String Tree

Some headstocks have one or more string trees, which reside between the nut and tuners. These route the strings at a sharper downward angle on the nut, for cleaner tone and better sustain on open notes.

Tremelo System - Whammy Bar and Bear Claws

Some bridges incorporate a tremelo system, which encompasses a number of additional guitar parts. It allows the pitch of the guitar to be altered, usually by a whammy bar - pushing on the bar moves/pivots the bridge closer to the nut, causing the strings to slack and lowering their pitch. Some bridges allow the bar to be pulled as well to raise the strings' pitch.

For bridges that use a whammy bar, the bridge needs counter-tension to prevent the strings from pulling the bridge away from its neutral position. Usually this is done inside a rear cavity where the bridge connects to bear claw springs. The springs are afixed to a metal clasp which is screwed into the body. Screwing the clasp further into the body increases the tension on the bridge.

Tremelo systems also usually include or require a locking nut or locking tuners. These prevent the strings from unwinding and rewinding differently during a heavy whammy bar dive, which would change the strings' tuning in the bridge's neutral position.

Bridge Saddles

All bridges have bridge saddles where there strings first touch the bridge - kind of like the nut. Most of the time these saddles are adjustable in some way. They can be raised or lowered to change the "action" of the guitar (which makes it more or less difficult to play at the expense of less or greater fret buzz). They can also be moved forward/backward to shorten/lengthen the string, which allows the instrument to be intonated (meaning it is in-tune across the entire fretboard). The tension/distance/mass relationship's effect on pitch is not as perfect as a simplistic model may assume - it is common for the thickest strings to require greater length than thinner strings, which is why it is favorable for the instrument to have a bridge with individual adjustable saddles.

Miscellaneous

Polepieces

Polepieces are the visible metal cylinders inside the pickups. Some pickups have covers that hide these, while others don't have individual pole pieces for each string but a single "rail" that spans all the strings. Some pickups feature adjustable height on the polepieces, or come preset with various heighths. I haven't found adjusting them has much effect on the tone, other than getting them close enough to acheive "pole pull" which is undesirable.

Pickguard

The pickguard is the plastic area on the face of the body that prevents you from scratching the finish on the body. These aren't that expensive and can find various designs/colors for most of the common guitar body shapes. The pickguard or "pickup rings" are usually how the pickups connect to the guitar body, and features screws to adjust pickup height. In some guitars, there is no pickguard or pickup rings and the pickups are screwed directly into the guitar body - they may or may not have springs underneath and be adjustible in this case.

Homework

Study your guitar and try to identify every single piece of it.

Q/A

Related Lessons

@@ Line 13: / Line 13: @@
 === Pickups ===
 ''Pickups'' are typically bars that reside between the bridge and the neck; however, they technically refer to anything that converts the string resonance into electricity.  Typical pickups are either ''single-coil'' or ''humbuckers''.  Humbuckers are usually wider than single-coils because they use two coils.  One is reverse wound, which makes any interference being picked up cancel out.  Humbuckers are also typically wired in serial, which gives them greater output but also greater impedance, which makes them a bit more nasal-sounding.  Single coils are associated with shimmering clean tones while humbuckers are a staple of heavily distorted tones.
+Additionally, there are piezo pickups that detect vibration without using magnetism, useful to get an acoustic-like sound.  And there are hexaphonic pickups that analyze each string and are typically used to convert the strings' motion into MIDI data.
 === Pickup-Selector Switch ===