What motivated D’Addario to re-engineer the manufacturing of steel music wire?



With the official launch of NYXL electric guitar strings around the corner, some of our customers have asked us why we decided to re-invent the process of making high carbon steel music wire.

The plain steel strings (unwound) and the hexagonal cores for wound strings are traditionally manufactured using a high carbon steel wire. High Carbon Steel (HCS) is a steel alloy with approximately 0.6% to 0.99% carbon-content. That’s less than 1% of the material in the alloy. Less than 1% doesn’t sound like a lot of carbon, but carbon content in this prescribed range makes for a material that can be drawn into the higher, spring-like tempers required for the core or unwound strings in a set of guitar strings. Anything under 0.6% carbon content is considered ‘medium to low-carbon’ steel; and while ductile and strong and useful for many applications (like the basis for the nickel-plated steel wire we wind around our HCS hex cores in our NYXL sets), it will not have the strength, memory and resilience to be used as a core wire or as an unwound plain string on a guitar.

Music string manufacturers have struggled for years to find the holy grail of high carbon steel and, unfortunately, have on occasion had to live with significant supply shortages. As a leader in the music string industry, we also have done extensive and quite expensive research to see if other materials like high-tech stainless and maraging steel alloys could be a higher performing substitute for HCS. All these efforts, while noble, have not yielded a successful substitute for high carbon steel, particularly for the unwound, plain strings on a guitar. While new alloys might meet and exceed some of the pull strength requirements, many are not ductile enough and fail when aggressively stretched or installed over a bridge saddle, nut, tuning machine or string clamping device. Nothing has been found to perform better than High Carbon Steel. We are constantly exploring new technologies and options and will continue to do so, but today HCS is the material of choice.

When I started my career at my dad’s company, Darco Music Strings, in the late sixties, pop music and garage bands were in the midst of an explosion like nothing ever seen. The sudden spike in demand for guitar strings and the wire needed to make them challenged the capacity of the few qualified specialty manufacturers of HCS wire.

At the time, the finest music wire (often referred to as mandolin wire) usually came from a handful of established suppliers in Worcester, Massachusetts. Worcester was sort of the ‘center’ for specialty wire drawing and finishing. The mills had workers that had developed trade secret processes to make very high quality HCS wire with beautiful tin coatings to prevent corrosion. These artisans were so skilled that they were able to make magnificent wire with antiquated machinery and tools.

In 1970, the EPA was formed and before long discovered that some of the processes being used, particularly in the tin coating of HCS, were quite hazardous. Dangerous chemicals like cyanides and hydrochloric acids in high concentrations were used to clean the wire before tin coating. Slowly as scientists and the EPA learned that these processes were hazardous, new regulations began to make it even more challenging for these artisans to produce high quality HCS, especially in the quantities that the market was beginning to demand.

All the factories making this material were, and many still are, using antiquated machinery, drawing die materials and inadequate quality control techniques. The result is that over the last 40 years, the music string industry has had to live with high reject rates of incoming HCS material and wide tolerance ranges in diameter, hexagonal cross-section shape (for core wires) and consistency of tin coating.

In 1979, D’Addario took a small interest in TruSpec Wire, a struggling startup HCS wire mill run by former employees of the National Standard Worcester Wire Works Company. Worcester Wire Works was the largest and most reliable source of quality ‘mandolin wire’ as they branded it. They had been in the process of making HCS for well over 100 years and were one of the bidders to supply the HCS for the cables on the Brooklyn Bridge in the 1870’s.

By the late seventies, their plant was rundown and EPA regulations were forcing them to re-tool and become compliant with all the regulations being instituted at the time. National Standard decided to move its Worcester Wire Works plant and after the move, they were never able to ramp quality and production up to where it was at their old plant.

The material shortage deepened and string makers were panicking to find quality suppliers. I personally took several trips to Germany and Sweden to try to develop new sources, but none of the plants there were equipped to draw, straighten and tin coat wire to the specifications we required. While learning a great deal, I was quite depressed at the state of all the vendors from which we had to choose.

As part owners of TruSpec Wire at the time, we began to incrementally improve their processes. In 1980, D’Addario did not have engineering or financial resources to accomplish what we have been able to accomplish today. However, we did make significant improvements to the process and managed to create a productive factory to supply our needs and the needs of some of our competitors.

As regulations became even more stringent, the manufacture of HCS became even more challenging. Recently, as several of our partners retired over time, we took full ownership of the HCS wire mill, which was still located in Massachusetts.

Ten years ago, an early win for us was switching from standard HCS raw materials to brass plated HCS raw material that is used in the steel-belted radial tire industry. The tolerances for automotive and aerospace tires being quite stringent, this material was far superior in grain structure and consistency and the brass plating improved our processes internally.

We quickly realized it made no sense to tin coat our hex core wires. There is microscopic brass plating on the raw material already, and we are ultimately covering the entire surface with a wrap wire when winding over the hex cores. Ten years ago, we stopped tin coating virtually all of the hex core wire we use for D’Addario strings. This improved product quality as the tin coating can cover some of the hex shape. The uncoated hex wire makes for more aggressive contact between the soft winding wire and the corners of the hex core shape. It also reduced our environmental impact as half the wire we consume is for hex cores and never gets tin coated. That means less chemistry, fewer fumes and less environmental impact.



You probably never noticed, but look closely at our wound strings and those of our competitors. If you compare the color of the piece of core wire extending past the winding, you will see it is ‘golden’ in color and most of our competitors are tin coated, thus a silver-like color.

What keeps us motivated and where are we headed next? Check back to see Part 2 of Jim’s Blog Post to find out!

The NYXL Story

Dear friends:

Fifty years ago anyone who liked music and was old enough to stay up and watch the Ed Sullivan Show on February 9th had their head spun around. In fact mine was almost spun off. That was the day that changed my life completely. From that point on, I was obsessed with learning to play guitar and learning to play every Beatle song that was already released and was to come out for the next seven years.

I was 14 years old and suddenly the family business talk at the dinner table became more relevant to me. I wanted to sound like the Beatles. I wanted an electric guitar like George’s. I wanted a Vox amplifier. Learning to play guitar was the mission. All along the way, the goal of learning and performing Beatles songs (and Stones, and Kinks, and Yardbirds and Byrds…..) never changed. Suddenly “the dog ate my homework” almost every day as I snuck after school to my friend Bob’s house to practice with my friends. Eventually we started to sound like a band.


Unlike today we were able to earn money playing gigs. People didn’t pass hats around, they actually paid the band a fee to play a party or a school dance. Imagine that! After each dance, the money was counted and as soon as we had enough, we begged one of our Mom’s for a ride to Sam Ash in Hempstead to see what new or used gear we could trade up to. I probably saw Jerry Ash as much as I saw my parents at that time.


Part of the process was also testing string ideas my Dad would bring home. He was a tinkerer. He didn’t have the scientists, engineers, laboratory equipment or time that we have to devote to research today but he had the curiosity; something that runs through the veins of the D’Addario Company to this day.

What he was doing was not too different from what we do today. He tried everything that was available through trial and error processes. Today, we have scientific methods to qualify what we are hearing, feeling and experiencing and more. And now we have the resources to develop new and superior raw materials of our own!

In 1965, I bought a used Stratocaster at Sam Ash and it needed new strings. It still had the standard, dead-sounding, semi-flattened, pure-nickel, original equipment strings on it. My Dad brought home some of the electric guitar strings that he was making. They were a pure round-wound string with a nickel-plated steel winding; the same round-wound formula he used to make Danelectro’s guitar and bass strings, and I was blown away.

The guitar woke up. It was bright, brash and loud, but balanced and clear. Suddenly it was easier to cut through and be heard.


I remember when the Stones released “Satisfaction.” Effects pedals were just starting to be developed. We didn’t have one and we had no idea how they got that sound on the guitar. In fact, at first we thought it was a saxophone. We had an Ampeg Rocket amp that we would turn up all the way to 10 (it didn’t go to 11) and overdrive the hell out of it to get the distortion we needed. It actually sounded great. Later, we used the same setup to play “Think for Yourself” by the Beatles.

But the strings were a critical component to the tone. They made my dead sounding Strat come alive. My Dad experimented all the time and this formula was tweaked to be the nickel-plated steel wrap wire that would eventually be introduced as Darco Funky Strings in the sixties and ultimately become D’Addario XL’s in 1974. The formula would also be adopted by every significant guitar string maker in the future. The most popular competitors’ electric guitar strings are direct descendants of this string specification.

Over the years all the string companies tinkered with different string constructions and alloys. Flat windings, Half-RoundTM windings, stainless steel windings, monel windings; you name it, we have collectively tried them all. Some of them have gotten traction and are an important part of the string selection today. But none have had the impact of those nickel-plated, round-wound strings that John D’Addario, Sr. created in the early sixties.

Until now.

Two years ago, we challenged ourselves to re-invent the electric guitar string and we have succeeded. We have created a new winding alloy, and have completely re-engineered the process of making music wire for the plain strings and hex cores of our wound strings. We didn’t grab something off a supplier’s shelf. With the help of the Town of Babylon, Suffolk County and New York State, we built a wire mill, right here at 540 Smith Street, Farmingdale, NY. You’re welcome to visit.

In the next few months, you will see the release of the next generation of electric guitar string. D’Addario NYXL, the strongest electric guitar string ever made. Named after New York because New York drive, determination and curiosity are what made it happen.

Recently we have sent out thousands of beta test samples tagged, #xlformula3. The consensus is coming in and the reaction is very similar to mine when I restrung my Stratocaster with Dad’s formula2 round wound strings in 1965. Check out the unfiltered Buzz yourself.

Soon the experience will be available to you. So standby as we fuel for the launch. Sign up for our newsletter so we can give you a heads up when they hit the street.