String (music)

What are Strings in Music?

In music, strings are long flexible structures on string instruments that make sound when they vibrate. Strings are stretched tight so they can shake freely. The pitch (how high or low the sound is) depends on how long, tight, and thick the string is.

There are two main types of strings: plain and wound. Plain strings are made from one piece of material, like nylon, gut, or steel. Wound strings have a thin center with other material wrapped around it.

Before World War II, many instruments like violins, lutes, and guitars used strings made from catgut, which came from animal intestines. Later, steel and nylon became popular because they could make different sounds. Wound strings, especially those made of steel, let instruments play lower notes with thinner strings.

This change helped instrument makers make thinner strings for low notes on instruments like the double bass. For instruments like the piano that use a keyboard to hit the strings, wound strings allowed builders to make smaller upright pianos that could still play deep bass notes.

String construction

One end of a string attaches to a tuning part on a musical instrument. This end is usually plain. The other end can be plain, loop-shaped, or have a small ball. This depends on the instrument. For guitars, this end helps keep the string in place. For violin family instruments, it keeps the string secure at the other end.

Strings can be made in different ways. Some have a round wire wrapped around a core. This is simple and inexpensive but can cause squeaking sounds and wear on the instrument. Others have a flat wire wrapped around a core. This is more comfortable to play and reduces wear but can be more expensive and harder to bend. There are also strings that mix features of both round and flat types. These offer a balance of comfort and sound. The core of the string can be either hexagonal or round. Each offers different benefits in stability and flexibility.

Gauge

The thickness of a string, called its gauge, changes how it sounds and feels. Thicker strings are heavier and need more pressure to press down on the fingerboard. Thinner strings are easier to press but might not stay in tune as well. For guitars, sets of strings often come in specific thicknesses, measured in thousandths of an inch. Electric guitars usually have thinner strings than acoustic guitars. Bass guitars also come with different thicknesses depending on their size.

Bowed strings

Since the 1900s, string makers have often sold strings for bowed instruments by how tight they are, not by their size. They usually offer three levels: heavy, medium, and light. But these levels can be different between brands, so one company's medium string might feel different from another's. Before 1900, strings were also sold in similar ways.

Some modern strings with a gut core and metal winding are sold by specific size measurements. A system called the Pirazzi meter, where one unit equals 0.05 mm, is used by some companies. For example, a string measured as 14 1/2 PM would be 0.725 mm wide. Some string brands still use the old heavy, medium, or light labels, while others use exact measurements in mm or the PM system.

Core materials

Steel is the main material for most metal strings. Some instruments, like the harpsichord and Gaelic harp, use brass. Other materials such as silk, gut, or synthetics like nylon and kevlar are also used.

Steel strings are popular for electric guitars and basses because they make a bright sound. Nylon strings, used for classical music, have a softer sound and need less tension, which is good for older guitars. Gut strings, made from animal intestines, were used long ago and some musicians still like them for their special sound.

Winding materials

Aluminum, silver, and chrome steel are used for violin and viola strings. Acoustic guitar strings are usually made with bronze, and piano strings with copper. Aluminum can be mixed with other metals to prevent damage from sweat. Classical guitar strings are made from nylon. Electric guitar strings are usually covered with nickel-plated steel. Bass guitar strings are made with stainless steel or nickel. Copper, gold, silver, and tungsten are used for some special instruments.

Some older strings have an open metal design. This style helps improve the sound of thicker strings. Examples of these open-wound strings date back to the early 1700s. "Silk and steel" guitar strings have thin silk threads under the steel winding.

Phosphor bronze was created by D'Addario in the early 1970s. It is said to keep its bright sound longer than other strings.

80/20 bronze strings are made from copper and zinc. The zinc gives these strings a brighter sound and extra strength. With a special coating, they stay better longer.

Some acoustic guitar players use strings made with nickel-plated steel.

Main article: String construction

String corrosion and prevention

Metal strings can get damaged over time because of a process called oxidation and corrosion. Metals like brass and bronze, which are often used in string windings, are especially prone to this. Oils and moisture from a player's fingers can speed up this damage. In steel strings, oxygen in the air reacts with iron to create rust, which makes the strings sound dull.

To protect strings, some are coated with special materials like polymer or plated with metals such as tin, nickel, gold, or silver. These coatings help keep the strings sounding good longer. Certain polymers, like Teflon, are very effective because they resist many harmful substances and keep the strings smooth and easy to play.

Some musicians boil their guitar or bass strings to clean them. Boiling helps remove oils, salts, and dirt that build up from playing. It can also loosen tiny metal pieces that get stuck in the strings, making them sound better again. However, boiling can sometimes make the strings a bit less flexible.

String vibration

Main articles: Mersenne's laws and Vibrating string

When a string is plucked or strummed, it moves back and forth. The main sound we hear is called the fundamental frequency. This sound depends on how thick the string is, how long it is, and how tightly it is stretched. This frequency decides the pitch of the note.

Along with the main pitch, we also hear other sounds called overtones. These are higher sounds that get quieter as they go higher. For example, if the main pitch is 440 Hz (the note A above middle C), the overtones might be at 880 Hz, 1320 Hz, and so on.

Sometimes a string can start moving on its own when other sounds around it match its natural frequency. This is called sympathetic vibration. In some music, like with electric guitars, musicians sometimes let the guitar make loud sounds. This can create cool effects in certain kinds of music.

Tensile properties

When you tune a stringed instrument, you put pressure on the strings. This pressure is called stress. The stretch or lengthening of the string is called strain. As you tune the string to a higher note, it gets longer and thinner.

If a string is stretched too far, it won’t return to its normal shape and can’t be tuned properly. Musicians want their strings to stay in the elastic region, where they return to their original shape after being stretched. This helps the instrument play well.