Authentic Acoustic SP® Guitar Strings 80/20 Bronze image number 0
Authentic Acoustic SP® Guitar Strings 80/20 Bronze image number 1
Authentic Acoustic SP® Guitar Strings 80/20 Bronze image number 1
Authentic Acoustic SP® Guitar Strings 80/20 Bronze image number 2

Authentic Acoustic SP® Guitar Strings 80/20 Bronze

5 out of 5 Customer Rating

Authentic Acoustic SP® Guitar Strings 80/20 Bronze

$7.49 - $18.99
5 out of 5 Customer Rating

Martin® Authentic Acoustic® Superior Performance SP® strings feature higher tensile strength and tin-plated core wire on all six strings that enable a fuller and more balanced tone, quicker response and increased tuning stability. Our impeccable standards for acoustic guitar tone are embedded in our string design and precision manufacturing process. That's why we make our own.

Authentic Acoustic SP® Guitar Strings 80/20 Bronze

  • Select styles for Availability
Gauge E B G D A E Tension Model
80/20 Bronze
Extra Light .010 .014 .023 .030 .039 .047 135.8 MA170
Custom Light .011 .015 .023 .032 .042 .052 153.7 MA175
Light .012 .016 .025 .032 .042 .054 167.3 MA140
Medium .013 .017 .026 .035 .045 .056 189.6 MA150
Extra Light 12-String .010/.010 .014/.014 .023/.010 .030/.012 .039/.018 .047/.027 261.7 MA180
Light 12-String .012/.012 .016/.016 .025/.010 .032/.014 .042/.020 .054/.030 324.0 MA190
Bluegrass .012 .016 .025 .035 .045 .056 179.8 MA240
92/8 Phosphor Bronze
Extra Light .010 .014 .023 .030 .039 .047 137.0 MA530
Custom Light .011 .015 .023 .032 .042 .052 155.1 MA535
Light .012 .016 .025 .032 .042 .054 168.5 MA540
Light/Medium .0125 .0165 .0255 .0335 .0435 .055 179.3 MA545
Medium .013 .017 .026 .035 .045 .056 190.9 MA550
Extra Light 12-String .010/.010 .014/.014 .023/.010 .030/.012 .039/.018 .047/.027 263.3 MA500
Silk & Steel Folk
Custom .0115 .014 .023 .028 .038 .047 122.2 MA130
80/20 Bronze
EL CL L BG M EL12 L12
E .010 .011 .012 .012 .013 .010/
.010
.012/
.012
B .014 .015 .016 .016 .017 .014/
.014
.016/
.016
G .023 .023 .025 .025 .026 .023/
.010
.025/
.010
D .030 .032 .032 .035 .035 .030/
.012
.032/
.014
A .039 .042 .042 .045 .045 .039/
.018
.042/
.020
E .047 .052 .054 .056 .056 .047/
.027
.054/
.030
T 135.8 153.7 167.3 179.8 189.6 261.7 324.0
92/8 Phosphor Bronze
EL CL L LM M EL12
E .010 .011 .012 .0125 .013 .010/
.010
B .014 .015 .016 .0165 .017 .014/
.014
G .023 .023 .025 .0255 .026 .023/
.010
D .030 .032 .032 .0335 .035 .030/
.012
A .039 .042 .042 .0435 .045 .039/
.018
E .047 .052 .054 .055 .056 .047/
.027
T 137.0 155.1 168.5 179.3 190.9 263.3
Silk & Steel Folk
CUSTOM
E .0115
B .014
G .023
D .028
A 0.38
E .047
T 122.2
EL=Extra Light
CL=Custom Light
L=Light
LM=Light/Medium
M=Medium
EL12=Extra Light 12-String
L12=Light 12-String

Behind the Design

A look at the New Martin Authentic Acoustic Strings.

Martin Strings

This is why we make our own.

How to choose a string gauge for your acoustic guitar

String gauge is an important part of playing and getting the best possible sound out of your guitar.
Here’s everything you need to know about acoustic guitar string gauges to make an informed decision about what strings are best for you.

Gauge refers to the diameter of a string. Gauges are described in thousandths of an inch and can be found listed on the back of a string pack.

Overall, string gauges are classified as:

  • Extra light
  • Custom light
  • Light
  • Medium
  • Heavy

For purposes of this tutorial we’ll refer to anything from extra light to light as “lighter,” and anything from medium to heavy as “heavier.” While we want this article to be a comprehensive overview of string gauges for acoustic guitars, it is important to note that Martin does not recommend heavy gauge strings for any Martin guitars. We recommend using only extra light through medium gauge strings on our guitars. Heavy strings can cause too much tension on the top which may cause irreversible damage.

If you’re just starting out, it’s not unusual that your fingers will have to toughen up a little. Lighter gauge strings will be more forgiving on your fingers as you’re learning, but as your dexterity and hand strength improve, you may find you prefer strings with different qualities.

Lighter

  • Easier to fret (important for beginners) and to bend
  • Better resonance under a lighter touch, common when first starting out

Heavier

  • Bigger sound - provide more volume and resonance
  • Better tuning stability - stays in tune longer

While string gauge is very much a matter of personal preference based on tone and feel, most manufacturers recommend string gauge based on body size. This is primarily due to the amount of tension exerted on the guitar top by the strings. In general, the larger the body, the more tension they can withstand.

Lighter

  • Exert less tension and are typically recommended for smaller bodied guitars such as 0, 00, 000, and OM, plus all cutaway models

Heavier

  • Exert more tension and are typically recommended for larger body sizes such as D, Jumbo, and Grand Jumbo

Certain techniques and styles of playing will demand different attributes from your strings and can impact which gauge you should choose.

Lighter

  • Good choice for rock, folk, country, and blues style playing with a lighter attack (plucking)
  • Allow for easier bending of notes
  • May break more easily with more aggressive playing styles

Heavier

  • Good choice for bluegrass and genres that require tuning down
  • Good choice for rock, country, and blues style playing with a harder attack

Are you playing for yourself in your living room? Or do you need your sound to reach the back of an auditorium? You’ll want to be sure to choose the right string gauge that will help you and your guitar sound the best.

Lighter

  • Offer appropriate volume and range for playing in an intimate setting

Heavier

  • Produces more volume and sustain
  • Great choice if you’re accompanied by other players

If you found yourself aligned with most of the qualities of “lighter” strings outlined here, choosing a string labeled “Light” is a good starting point. If you’re finding finger-fatigue is an issue, or you wish it was easier to bend notes, try extra light or custom light gauge strings.

If most of the qualities prescribed to heavier strings appealed to you, start with strings that are labeled “Medium.” While Martin does not recommend using heavy gauge strings on Martin guitars, we want to paint a complete picture of string gauge options. Some guitarists use heavy gauge strings for amplification, sustain, drop/down tuning, or tuning stability reasons.

One thing to keep in mind when trying out a new string gauge is to make sure your guitar is set up correctly for the gauge you're playing. Things like fret buzz can be a symptom of needing to visit a luthier to have your guitar adjusted.