Acoustic Guitar Strings vs. Classical Guitar Strings

The first basic distinction to make is the difference between classical and flamenco guitars fitted with nylon strings versus steel string acoustics—the type associated with rock, folk, country, and blues. In most cases their strings are not interchangeable. Using steel strings on a guitar built for use with nylon strings can seriously damage it. The neck construction and top bracing of classical and flamenco guitars are not designed to handle the far greater tension produced by steel strings. Using the wrong strings can also damage the bridge and saddles.

Acoustic & Classical Guitar

All About Acoustic Guitar String Gauges
Before we dive into the specific characteristics of various types of acoustic and classical guitar strings, let’s address the question of gauges since it applies to both types. Acoustic strings are manufactured in a range of thicknesses or gauges. These gauges are designated in thousandths of an inch. The lightest strings are typically .010 and the heaviest a .059. String gauge has a big influence on playability and sound. Most acoustic guitars ship with light or medium gauge strings, which are also known as 12s or 13s.

Note that classical guitar strings are also designated according to their tension. We will discuss the effect of tension on classical guitar playability and performance below.

Lighter gauge strings:
are generally easier to play
allow easier bending of notes and fretting
break more easily
produce less volume and sustain
are prone to cause fret buzzing, especially on guitars with low action
exert less tension on the guitar neck and are a safe choice for vintage guitars

Heavier gauge strings:
are generally harder to play
require more finger pressure to fret and bend notes
produce more volume and sustain
exert more tension on the guitar neck