THE GUITAR Presented by Jerry Yin

Demonstration by Abel Debalkew

OVERVIEW The Guitar and its Origin Basics of Sound Parts of a Guitar

StringsTuning PegsGuitar BodySoundhole

Conclusion Quiz

THE GUITAR 6-stringed instrument played by plucking/strumming with fingers or a pick most popular instrument of the string family the first guitar was created over 4000 years ago

Tanbur Lute Dotar 4-String 5-String

6-String

BASICS OF SOUND sound is energy in the form of waves caused by vibration travels in longitudinal waves

a wavelength of a sound wave is one complete cycle of the wave at two equal successive points

amplitude is the height of the wave; the higher the amplitude the louder the resulting sound

frequency is the number of cycles that pass a certain point per second in a sound wave; the pitch of the sound

PARTS OF A GUITAR

THE STRINGS made of nylon or steel stretched from the bridge of the guitar against the nut and

into the tuning pegs, over the frets strumming or plucking the strings causes them to vibrate,

causing the surrounding air to vibrate the frequency of the string is determined by three factors;

mass: the heavier the string, the slower the vibration tension: the tauter the string the higher the pitch length: the shorter the string the higher the pitch

HARMONICS when a string is plucked, there are parts of the string that don’t

vibrate (nodes) and parts that do vibrate (anti-nodes) when the string has only two nodes (the nut and the bridge) we

hear the fundamental frequency when you create new nodes with your fingers, the frequency

and amplitude of the sound can be manipulated; these are called harmonics.

TUNINGhttps://www.youtube.com/watch?v=JLI7GxVIo1M

1:28~2:17

GUITAR BODY made out of wood (mahogany, maple, spruce) the guitar body amplifies the sound of the strings the bridge of the guitar body is in contact with the strings,

causing it to vibrate when the strings vibrate; consequently this causes the top plate of the guitar (soundboard) to vibrate as well

the soundboard is made out of a thin plate of wood and amplifies the sound greatly due to its broad surface area

SOUNDHOLE when the soundboard vibrates the air inside the body

of the guitar vibrates as well, causing all the air within the guitar to vibrate at the same frequency (resonant frequency)

this vibrating air escapes the guitar through the soundhole, allowing the sound to travel to our eardrums

INSIDE OF A GUITAR

IN A NUTSHELL strings on a guitar are fixed at either end and are what

cause the sound; frequency is affected by the mass, tension and length of the string

different harmonics can be achieved depending on the guitarists fingering upon the fret board

the strings vibrate the bridge of the guitar body, which cause the entire guitar to vibrate as a system, and the sound escapes the inside of the guitar through the soundhole.

QUIZ

QUESTION ONEWhat factors affect the frequency of a guitar string? Describe their relationships.

Answer:mass: the heavier the string, the slower the vibrationtension: the tauter the string the higher the pitchlength: the shorter the string the higher the pitch

QUESTION TWODescribe the process of how sound is produced from the guitar (beginning from the strings).

Answer: When plucked or strummed, the strings on a guitar begin to vibrate. Since the bridge is in contact with the vibrating strings, and it is attached to the top of the guitar body (the soundboard), the vibration of the strings causes the entire guitar to vibrate as a system.

QUESTIONS?

WORKS CITED http://www.bsharp.org/physics/guitar http://entertainment.howstuffworks.com/guitar1.htm http://

guitar.about.com/od/helpbuyingguitarsgear/a/gtr_soundboard.htm

http://www.physicsclassroom.com/Class/sound/u11l1c.cfm

http://www.physics247.com/physics-tutorial/guitar-string-harmonics.shtml

http://www.guyguitars.com/eng/handbook/BriefHistory.html