Violin strings are made from one of three core materials: animal gut, synthetic nylon (most commonly a type called Perlon), or steel. The outermost layer you actually touch is usually a thin metal winding wrapped around that core. Each combination produces a different tone, and most violinists today use synthetic-core strings as their default choice.
The name “catgut” has confused people for centuries, but no cats were ever involved. The word likely comes from “kitgut,” where “kit” was a dialectal term for a small fiddle, not a kitten. Over time, the words got tangled together.
Gut Strings: The Original Material
The oldest type of violin string is made from sheep intestine, a tradition stretching back to ancient Egypt. Only one layer of the intestine is actually useful: a thin, fibrous membrane sandwiched between the outer and inner linings, both of which get scraped away. The manufacturing process is painstaking and still done largely by hand at a few specialized workshops.
Fresh intestines arrive from the butcher while the carcasses are still warm. Workers stretch them on an inclined surface and scrape them clean of fat and debris, then bundle them and soak them in cold water for 12 to 15 hours. After a second soak in tepid running water, a mild fermentation begins, which helps separate the fibrous membrane from the two useless outer layers. Women historically performed the next step: scraping each intestine with a split cane on a wet, angled slab until only the muscular fiber remained.
These fibers then go through repeated chemical baths over two to three days, alternating between alkaline solutions and mild acid, with hand-rubbing between each soak to remove any remaining tissue fragments. Because natural intestines aren’t perfectly uniform in diameter, makers often split them into long threads with a specialized knife, then twist multiple threads together to achieve the right thickness. The result is a string with a warm, complex tone that responds beautifully to bowing, but one that’s sensitive to humidity and temperature. Gut strings take about a week to stretch and settle before they hold their pitch reliably.
Synthetic Core Strings
Synthetic-core strings were introduced roughly in the 1970s and have steadily taken over. The most common core material is Perlon, a type of nylon polymer. These strings were designed to mimic gut’s warm, rich sound while eliminating its biggest drawbacks.
The practical differences are significant. Synthetic strings stabilize in pitch after just a day or two instead of a full week. They hold tune far better through changes in temperature and humidity, and they respond faster under the bow. For these reasons, Perlon-core strings are now the most popular choice among both students and professional classical players.
Steel Core Strings
Steel-core strings use a thin wire of high-carbon steel at their center. They produce a bright, focused tone with excellent pitch stability and fast response, but they sacrifice some of the warmth and tonal flexibility that gut and synthetic strings offer. The steel core also makes the string feel harder and stiffer under the fingers.
The violin’s highest string, the E string, is almost always plain steel, even when the other three strings have gut or synthetic cores. Carbon steel is the most common base material for E strings. Some E strings use a single solid wire, while others use a more complex rope-like core for added flexibility. The choice between a steel A string and a synthetic A string is one of the most common decisions violinists make when mixing string types across their instrument.
What the Outer Winding Is Made Of
Except for the thin E string, violin strings are wound with metal wire to add mass. This extra weight allows the thicker strings (A, D, and G) to vibrate at the correct lower pitches without becoming so thick that they’d be unplayable. The winding material has a direct effect on both the sound and the feel of the string.
- Aluminum is the lightest winding metal, with a density of just 2.7 g/cm³. It’s used most often on violin and viola A strings, where you want to add mass without making the string too heavy or sluggish.
- Silver is much denser at 10.5 g/cm³, making it ideal for the lower G and D strings. Silver can tarnish when exposed to sulfur in the air, especially under UV light, but the discoloration is purely cosmetic and doesn’t affect the sound.
- Chrome steel (technically a chromium-nickel alloy, since pure chromium is too brittle to work with) offers high corrosion resistance and a bright tone.
- Tungsten is exceptionally heavy at 19.3 g/cm³, as dense as gold. Because it’s extremely difficult to flatten into the thin ribbon needed for an outer layer, tungsten is used as a hidden inner winding between the core and the outer metal. It lets makers build very thin strings that still have enough mass for deep, low pitches.
Most wound strings have the metal applied in two forms. A round wire wraps directly around the core, and then a flat ribbon of metal wraps over that to create the smooth surface your fingers slide along. Some strings add a layer of silk thread between the core and the winding to dampen vibrations slightly and change the tonal character.
Plating on the E String
Because the E string is unwound, its surface coating matters more than on any other string. Most E strings start as carbon steel wire and then receive a thin plating of another metal.
Tin plating is the most common. It resists corrosion reasonably well and produces a bright, clear sound. Gold plating adds warmth to that brightness, blending projection with a rounder tone. Platinum plating offers the widest range of sound colors and strong projection, with a surface that feels stable under the fingers during shifts and vibrato. Plain, unplated chrome steel E strings exist too, delivering a brilliant tone but with less corrosion protection.
One practical issue with E strings is “whistling,” an unpleasant high-pitched squeal caused by the string vibrating and twisting at the same time. Switching from a gold-plated chrome steel E to a tin-plated carbon steel E often reduces whistling, though the trade-off is that tin-plated strings corrode faster and can feel rough as they age.
How Players Choose
Most violinists don’t use one type of string across all four positions. A common setup pairs a steel E string with three synthetic-core strings for the A, D, and G. Some soloists still prefer gut D and G strings for their warmth and complexity, accepting the extra tuning maintenance as a worthwhile trade-off. Jazz and folk players sometimes favor steel cores for their volume and projection in amplified settings.
String choice also depends on the instrument itself. A violin with a naturally bright, edgy tone might benefit from the warmth of gut or synthetic strings, while a darker-sounding instrument can come alive with the clarity of steel. The winding metal, the core material, and any surface plating all interact with the wood’s natural resonance, which is why violinists often spend years experimenting before settling on a preferred combination.