Acoustic Guitar Strings: What You Need to Know

What You Need to Know About Acoustic Guitar Strings…

Jazz Guitar Today continues our series on strings with Brian Vance, Director of Product Development for D’addario & Co. This time Brian discusses Acoustic Guitar Strings.

First, I’d like to take a brief moment and thank everyone who commented on my last string article. It’s rewarding to see there are some string geeks out there and engaged players who appreciate the not-so-subtle differences between strings and how they can impact your performance. Personally, I took strings for granted until I worked for D’Addario and have since learned just how important strings are to the guitar ecosystem what a difference they can make. I love sharing what I’ve learned and hopefully, I’m providing some inspiration and interesting ideas for experimentation. I like to say that taking a $10 chance on strings can change your life. So, on that note, let’s maybe change some lives here… Brian Vance

While there are similarities between acoustic guitar strings and electric strings in terms of core and plain steel materials and construction, there are clear design aspects specific to acoustic strings.

Not to diminish the importance of strings on an electric guitar, but with acoustic guitar strings, the marriage between strings and instrument is much closer and critical. With electric strings, their loss of tone over time is more gradual and not as immediately impactful on your guitar’s tone (a tweak of your tone or gain knob might do the trick to liven things up), but an acoustic instrument’s sound and performance can live or die by the strings on it. So, it’s critical to understand not only the strings you are using, but also the condition they are in and how it can be affecting your instrument’s sound and performance.

If you refer to the previous article, string elements such as the ball end and core wire are generally similar or the same between acoustic and electric. And while there are some variations in acoustic string construction, the vast majority of acoustic strings are round wound. This construction type delivers the most volume, resonance and harmonic complexity. Volume and resonance are extremely important to an acoustic instrument as the strings are required to generate energy in order to produce sound, a very different dependency vs. magnetism and pickup interaction (however, there are times when magnetism is relevant for acoustics instruments, but more on this later). 

First, a little guitar string history…

While the modern acoustic/classical guitar likely dates back to the 1850s, the development of the archtop acoustic guitar in the late 1800s by Orville Gibson changed everything.

This body style produced more volume to the point where the guitar could now compete with banjos and horns in the orchestra. There is a much-documented history on this, so I won’t go into the details, but the importance of this advancement can’t be overstated, particularly as it relates to string development. These guitars could handle more tension and therefore heavier gauged strings (primarily made of steel at the time – vs. nylon), which were now a requirement to achieve maximum volume and projection. To accommodate this need for increased tension and volume,  steel, copper, silver-plated copper, “commercial bronze (90% copper and 10% tin and other alloys)” and Monel (trade name for a nickel-copper alloy) all were used to varying degrees of success. 

Then, sometime in the 1930s, John D’Addario Sr. met John D’Angelico. Both were New Yorkers who were part of a small, but growing musical instrument business.

By 1937 they had collaborated on pioneering not only standardized string gauges (light, medium, heavy, etc.), but more importantly, the use of a new alloy for strings which was ideally suited for the acoustic guitar. That alloy was 80/20 bronze (it’s not really bronze, but more commonly known as brass), which is composed of 80% copper and 20% zinc. The additional amount of zinc (vs. the aforementioned 90/10 commercial bronze) created a brighter, louder string than the traditional softer sounding alloys and harsher sounding steels. 80/20 brought out an impressive acoustic warmth, rich harmonics and broader breadth of tone (more highs and lows), which became the standard for nearly 4 decades. Guitarists have these greats to thank in part for where we are today!

80/20 remained the standard until the early 1970s…

Then in1974, Jim D’Addario first utilized phosphor bronze (92% copper, 7% tin and 1% phosphorous, sometimes referred to as 92/8) for guitar strings. Phosphor bronze offers an optimal balance between warmth and brightness while preserving string tone longer – you could call it the first extended life string. Today, phosphor bronze is the most popular acoustic string alloy and would be considered by most to be the standard.

Acoustic Friendly Materials

There are also many other acoustic-friendly materials available today that offer a variety of tonal options from warm to bright, increased lifespan, softer feel, tension options, etc. Here are a few popular options to consider;

• Silver plated copper – traditional acoustic alloy with a base of copper plated with silver on top. Think about plated wrap wire as having a solid inner section with a thin outside sheath. SPC is warm and mellow, ideal for classical and folk style tone, but is prone to tarnishing quickly. Preferred for Classical guitar, Gypsy Jazz guitar and folk fingerstyle sounds.
• Monel – traditional acoustic alloy comprised of nickel (63-67%) and copper (27-34%) with traces of iron, carbon, manganese and silicon. Warm, “broken in” tone with fairly strong corrosion resistance.
• Nickel bronze – nickel plating over phosphor bronze offers enhanced clarity, improved projection and improved string life. These strings are a great option for jazz playing. The nickel bronze alloy projects the middle strings (D and G in particular) more in the mix and improves the volume balance between the wound and plain strings, all of which is great for single note lines and soloing. 
• Aluminum bronze – aluminum and copper alloy offers enhanced clarity, volume and strong corrosion resistance.
• 85/15 – another variant alloy composed of 85% copper, 15% zinc. Tonally, it subtly fits somewhere between Phosphor Bronze and 80/20, but is technically closer to 80/20 in most ways.
• Stainless steel – while primarily an electric string alloy that lacks in acoustic warmth, some prefer stainless steel for its unique brightness, projection and long string life. 
• Nickel-plated steel – believe it or not, similar to stainless steel fans, there are some who prefer electric strings on their acoustics. I know of several bluegrass flatpickers who swear by a set of D’Addario EJ22’s (similar to a medium acoustic set) on their acoustics, claiming the strings allow the instrument to speak without the string coloring the inherent wood characteristics.

The bottom line is, it’s good to experiment depending on what kind of string tone you prefer and how important string life is to you.

As mentioned, generally, Phosphor Bronze is the preferred choice, but there are options for a reason and different players have different needs or preferences.

In many cases, players who have trained ears or very specific needs will use different strings and string gauges on different guitars. Personally, I love 80/20 on my Larrivee parlor guitar, nickel bronze on my Eastman slope-shoulder dreadnought and XT coated phosphor bronze on my main gigging acoustic/electric guitar (Takamine). This comes from years of experiment and trial and error, so I encourage you to invest a little time and dough into exploring – remember, $10 can change your life! You never know til you try.

Coated or Uncoated Acoustic Guitar Strings?

I mentioned string life… extended life and/or coated strings are a part of the arsenal for many players these days. This is particularly important for acoustic strings, which are much more susceptible to corrosion than electric strings. I know players who can kill a set of uncoated acoustic strings in 30 minutes, let alone a full gig. The quality of coated strings today is pretty outstanding. If you haven’t tried modern coated strings or you tried them in the past and didn’t like them because they altered tone or feel, I strongly suggest you consider or reconsider. Coating technologies and treatments have come a long way in the past 10 years, all with the player’s needs and demands in mind. Delivering an uncoated string tone and comfortable feel (either natural or slick, your preference) is mandatory in the string business today and there are many options to consider. Not surprisingly, I’m personally biased towards D’Addario’s new XT strings, but companies such as Elixir, Ernie Ball and Martin wouldn’t be competitive today if they didn’t make a quality product. In the case of coated strings, it might take $15 to change your life, but a small price to pay in the long run.

Acoustic String Construction

As mentioned, Round Wound is the standard for acoustic strings, but there are other options and variants for different applications. Here are a couple of interesting construction options –

• Flattops – a D’Addario innovation where they softly flatten the tops of a round wound phosphor bronze string. This is a similar effect as our Half Round electric strings, delivering a smoother feel and reduced finger noise. Some acoustic slide players and bluegrass flatpickers love these strings!

• Silk and Steel – a silver-plated copper wrap wire is wound onto a steel core with inner windings of nylon filament material (no longer silk, technically, but the name has stuck over time). These strings are softer to the touch with less tension and a smoother feel than traditional acoustic strings. Ideal for some fingerstyle steel-string players who want more of a nylon/classical tone.

The last key topic surrounding acoustic guitar strings is gauge.

Today’s wide variety of guitar body styles and shapes, wood types, musical styles, altered tunings, etc. creates the need for a multitude of gauge options. While standard gauges are pretty consistent for the masses (light, medium, heavy, etc.), there are more options than ever. One thing to keep in mind is that even though there are general standards, there can be variations between brands in terms of how they name their gauges. Here are the D’Addario 6-string standards, but these might not always translate, so when shopping, make sure to look at the gauges numbers themselves, not just the gauge name;

• Extra Light 10-47. This is a good gauge for beginners to get started with, but can also be great for recording. The lighter gauges compress well through microphones when strummed and create a smooth, even textured recorded acoustic sound. 
• Custom Light 11-52. This was Jim D’Addario’s personal choice of gauges, so he created this custom set to his liking, hence Custom Light.
• Light 12-53. The most popular selling acoustic string gauge. An ideal balance of comfort and volume. 12-53 gets the job done for most, but as one example of gauge variations between brands, some company’s offer 12-54 as light gauge.
• Medium 13-56. Preferred for its increased volume and fullness. Not for the meek, these strings require more hand strength to realize and appreciate the benefits. Also, some players who tune down a ½ or whole step find this set useful. 
• Light Top/Medium Bottom 12-56. Also known as the “Bluegrass” gauge since many flatpickers like to solo on lighter plain steel strings, but prefer the deep low end and volume of Medium gauge strings for rhythm playing. Good option for Drop D, as well.
• Heavy 14-59. Only a small percentage of players go this heavy in standard tuning, but they are popular for down or altered tunings.

Exploring More Gauge Options

“Standard” string gauges evolved over time primarily through trial and error and personal preferences by guitar builders and artists. However, there is some science and mathematical relationship between the string gauges within a set. Sometimes the math works and sometimes it doesn’t. In the case of acoustic strings, it’s a bit of a mixed bag vs. the relatively easy application to electric strings.

D‘addario Tip: After a lot of work, analysis and testing (similar to our approach with electric guitar and bass strings), D’Addario developed Light and Medium gauge Balanced Tension sets in their Nickel Bronze line. These sets are designed to be more mathematically balanced in tension/feel across all strings within the set. The specific string gauges for acoustic might seem a bit unorthodox at first, but over time, some players get hooked on the feel and improved volume balance between the strings. 

There are also gauges designed around specific tunings…

D’Addario’s EJ24 DADGAG set offers the A, D and G strings of a Light set with the Low E, B and high E of a Medium set. So, when you tune down to DADGAD, the set has a comfortable, overall balanced tension and optimal string-to-string volume.

High-strung/Nashville Tuning. Try this!  String up a second acoustic with this set. It’s essentially a prepackaged set of the octave strings from a 12-string set. When used in recording can add a lush shimmer and chorus/12-string effect when doubling parts. Pan them in stereo or blend them together, amazing effect!

Gypsy Jazz. This is not just a different gauge, it’s a completely uniquely constructed string. Given Gypsy Jazz guitars have a longer scale length and the desired tone is somewhat more “spanky” (sorry for the lack of a technical term), these strings are lighter cores and overall gauges and wound with silver-plated copper. This combination produces a very unique sound, specific to the Gypsy Jazz style. Additionally, traditional/vintage Gypsy Jazz guitars have tailpieces that require loopend strings, whereas many of the newer generation of guitars can handle loopend or ball end strings. 

Amplifying Acoustics: Acoustic vs. Electric?

This topic probably requires in-depth exploration as there is a whole science to amplifying acoustics and how strings interplay with microphones, piezo pickups and magnetic pickups, but as far as acoustic strings go, here is an overview of all three;

1 – Microphone systems act exactly the same way an external microphone would work, picking up the sound of the strings (tonal qualities and volume) and sending that signal to a preamp or amplifier.

Standard acoustic strings work just fine in this environment and the type of alloy, gauge, etc. can have a noticeable impact on tone.

2- Piezo pickups, generally crystal elements or film under the saddle, sense physical vibration and convert that into voltage.

String vibration is critical to a quality piezo signal and the gauge (more mass, more energy), thick string coatings, or “dead” strings (more damping, less volume) can all negatively impact interaction with the piezo. My personal experience and perception are that differences in string alloys are somewhat minimized due to lack of actual tone being passed through the piezo sensor, but I don’t have any science or data to back that up. A fresh, bright string can really fire up a piezo and in contrast, an old tired string can really sound flat and dead through a piezo, so it’s important to keep strings strings fresh – garbage in, garbage out, as they say.

3 – Magnetic pickups are also commonly used to amplify acoustics.

Technology and tone quality of acoustic magnetic pickups has come a long way since Gibson put a P-90 into a J160E in the 60s. Today, magnetic technology has been optimized to create faithful, warm and rich acoustic tones utilizing traditional acoustic strings. So, how does an acoustic string work with a magnetic pickup? The trick is to build an effective magnetic system around 4 wound acoustic strings that have little ability to affect a magnetic field. If you recall from the first strings article, the copper-based alloys that are most popular for acoustic strings are non-ferrous (unlike the steel and nickel-plated steel in electric strings) and not well-suited for magnetic pickups. That said, the inner core material of acoustic strings is made of the same high carbon steel material used in electric strings. This material under the windings is highly magnetic, so a pickup can get some “signal” from the core of wound acoustic strings.

What most magnetic acoustic pickups do is to compensate magnets (more magnetism on the wound strings, less on the plain strings) or vary the distance of the magnets between wound vs. plain steel strings (magnets are placed further away from the plain steels) to achieve a balanced acoustic sound. In contrast, if you played an electric string set through an acoustic magnetic pickup the balance would likely be off. I will leave the proper science and technical explanation to the acoustic pickup experts, but hopefully, this is all makes sense.

OK, that concludes our acoustic guitar string class for today…

Hopefully, you’ve learned something. By compiling all of this information, both historical and technical, I sure did. The next edition of this series will be focused on nylon/classical strings, so stay tuned for more.

View More in the Guitar Strings Series:

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