Nylon Strings (náylɑ̀n strɪ́ŋ) are the strings of choice for classical guitars. The three thinnest nylon strings, known as the treble stings, are made of clear or rectified nylon. The three thickest strings, the bass nylon strings, are usually wrapped in a metal, such as bronze or silver plated copper. Treble nylon strings are said to have a sweeter tone than strings made out of other materials. The most popular string length for a classical guitar is 650 mm. Steel strings should never be used on a classical guitar, because they can damage the instrument.

Nylon is a synthetic polymer that was first used as a substitution for silk. It’s superior in sound quality and durability than the gut strings that used to be used on classical guitars. Nylon guitar strings are extruded, which means they’re drawn through a die in one long string. Clear nylon strings are monofilaments and rectified nylon strings are very precisely ground to be one diameter down the length of the string, giving them a richer sound.