Martin Authentic Flexible Core Phosphor Bronze Acoustic Guitar Strings

Martin® Authentic Acoustic® Flexible Core Strings are crafted for players who demand comfort without compromising tone. Designed with a unique construction—featuring a lighter gauge Superior Performance core wire paired with a heavier wrap wire—these strings provide a softer playing feel while delivering a full, rich, and balanced tone. The added flexibility makes them ideal for expressive playing styles, including wide bends, fast runs, and long practice sessions, all with reduced finger fatigue.

Built to Martin’s uncompromising standards, these strings are the result of in-house engineering, precision manufacturing, and a deep understanding of what acoustic tone should sound and feel like. Whether you're strumming or fingerpicking, Martin Flexible Core strings offer a dynamic response and consistent performance that brings out the best in your guitar.

Features:

• Flexible core design reduces finger fatigue and enhances playability

• Full, balanced tone with excellent projection and clarity

• Superior Performance core wire for long-lasting durability

• Ideal for expressive playing styles and big bends

• Precision-engineered in-house by Martin for uncompromising tone quality

Specs

• Core lighter gauge Superior Performance wire

• Wrap heavier gauge bronze or phosphor bronze (varies by model)

• Tone profile rich, balanced, and dynamic

• Playability enhanced flexibility for easier fretting and bending

• Ideal for acoustic players seeking comfort and tone

• Manufacturing precision-made by Martin

• Available types 80/20 Bronze and Phosphor Bronze

• Gauge options light, custom light, medium