Why Do Different Guitar Strings Make Different Sounds?

Bass Strings

The three lowest strings on a guitar (E-A-D) and sometimes the fourth (G) are wound, which means that an additional layer or metal is wrapped around a core length of metal string. This causes the strings to vibrate at a lower frequency.

Treble Strings

The top three (G-B-E) (and sometimes only the top two) strings of a guitar are unwound, causing them to vibrate at higher frequencies than the bass strings.

Diameter

The diameter of strings also affects the pitch produced by the open strings. The low E-string is thick, while the high E-string is several times smaller in diameter. Each string in between represents a gradation in diameter.

Tuning

By increasing or decreasing the tension on a string through tuning, the obtained pitch is affected. For instance, if the E-string is slackened to D, it vibrates at a lower frequency, while if it is brought up to F, it vibrates at a higher frequency.

Fretting

Additional tension is applied guitar strings by fretting, or placing the fingers at preset points along the string. Fretting always causes the pitch of a string to go up.