What Are Piano Strings Made Of

What Are Piano Strings Made Of? How Piano Strings Are Made

What are piano strings made of? What are the best brands for piano strings replacement in the market? If you are curious about how a piano string is made and what are the best strings to replace your old ones, join us as we discover all the things needed to answer these questions.

History Of Piano Strings

A piano string comes from a special wire that is usually made of tempered high-carbon steel, which is also known by many as spring steel, as it replaces iron as the original material in making one since 1834. Piano strings are known to have a high tensile strength as they are meant to withstand the heavy stress that is placed upon them.

The first recorded making of these wires was in 1351 in Augsburg. As time went by, innovations and new methods were discovered to make this instrument accessory stronger and more durable than before. Nowadays, each of the piano strings can handle 75 to 100 kilograms of tension, so all in all, it can have around 20 tons of tension, which is pretty impressive.

Over the last 20 years, the advancement in making piano strings has primarily improved, thanks also to the development of computers and artificial intelligence. With the help of newer technology, it allows the piano strings to produce a more improved sound while being more durable compared to older piano strings. As computers can quickly analyze what the best materials to be best used in making piano strings are, it could also result in companies producing the best piano strings when it comes to quality. 

What Are Piano Strings Made Of?

Today, most piano strings available in the market are made of the same materials: copper and high-carbon steel. These two materials are known to be durable, long-lasting, and have the ability to keep up with the tension that is needed in every piano, so they won’t be able to break quickly. They can also produce a consistent sound, which is highly necessary for stringed musical instruments, such as the piano.

Usually, the treble and middle of a piano utilize three carbon steel strings per note, and its bass section uses a carbon steel core with copper winding. Their wound is similar to a guitar string, resulting in a more solid core and an outer winding around the string, giving it the ability to handle more tension. The piano strings get thinner for the higher pitch section on the piano, while it gets thicker when it comes to the lower-pitched notes.

How Piano Strings Are Made

In a typical piano setup, there are two different types of strings that come with it. For the top 2/3 part of the piano, manufacturers use plain steel as its primary manufacturing material, while on the bottom 1/3 part, they usually use piano strings with a steel core wire that is wrapped with copper, resulting in it producing a lower tone.

To start making a piano string, the first process it goes through is called austenitizing. It heats up the steel, which is the primary material for the strings, up to 2,000 degrees before cooling them again. This process will result in the steel changing its structure. Rapid cooling of the steel after it goes through high heat temperatures will allow it to set its structure.

The next step is to press the steel into a funnel or also called by others as die. When its diameter shrinks up to 30% from before, the steel is pulled from the funnel. This is a repetitive step, so when the steel gets reduced, its fibers or grains also get compressed. As you heat up, the grain starts to open up, while cooling will result in setting the structure of the steel.

All in all, there are at least three times that the steel will go through the heating process and will be drawn four or more times to shape it to its final size.

Most manufacturers also use nickel electroplating on their piano strings as the last part of the process, as this will serve as protection from corrosion and rust. However, as the plating is very thin, the piano strings will still rust over time, especially if it is made of steel. Although it can affect the tone a little bit, it would be better to prioritize the longevity of the piano strings.

What Makes A Great Piano String

When it comes to choosing a great piano string to replace your old ones, there are three things that you should highly consider: the first is its raw material; the second is whether it is perfectly round wire, and the third is the consistent and correct tension of the copper that is used in wrapping around the steel.

It is highly important the material used in making the piano strings are of high quality, as this will ensure that it will produce a consistent top-quality sound while having the durability to last for a long time without having to replace them. For the third reason, it is highly applicable to making the bass strings of the piano.

Without being able to complete these three necessary factors in making high-quality piano strings will result in unwanted vibrations, making it unbearable to listen to. If its roundedness is also not perfect, it can lead to a distorted sound, which can really be a hassle, especially since it is not easy to open up a piano just to replace its strings.

Top Piano String Brands


One of the leading brands in the industry, the Roslau piano strings are all made in Germany, and they are widely known for their accurate and uniform roundness and thickness. They also have higher tensile strength compared to other piano strings. There are also some piano manufacturers who use Roslau strings on their products, especially on their higher-end pianos.

Stephen Paullelo

Since it started making high-quality piano strings in 1996, the company has been one of the most successful in the industry, making them one of the go-to options for technicians who change piano strings for their clients. Their piano strings are available in two finishes: nickel-plated and regular. They use five different types of steel that come in different resistances; however, Stephen Paulello is able to manufacture them in the same scaling called the Hybrid scaling.

The hybridization principle integrates several types of steel within the same scaling to harmonize and optimize the stress rate throughout the piano. To master the stress rate, it also means that you will have to enhance the richness of the sound and balance the tones. With Stephen Paullelo’s Hybrid scaling, they can become more stable and become easier to tune.


Since the company’s establishment in 1912, Mapes has been known for making high-quality piano wires that come with most of the high-end acoustic pianos nowadays. For more than 100 years, they have established a reputation for producing top-notch piano strings, so there is no doubt that they are included in our list. You can see Mapes strings in many Steinway & Sons pianos, which is a highly known brand for making premium acoustic pianos.

So, what are piano strings made of? When it comes to piano strings, there are two materials that are usually found in most that are available in the market: high-carbon steel and copper. Not only known as durable, but they are also famous for being able to help in producing a consistent and pleasant sound for the piano.