Tips & Tutorials | May 12,2022

Where the Rubber Meets the Road

Tommy Emmanuel on Martin’s Flexible Core Strings

by David Schneider

I recently took my car to the shop with a heavy heart and grim expectations. It seemed like there was some kind of major problem: It was shaking at higher speeds, veering inexplicably to both the left and right, and generally acting weird. Since I've chosen to remain willfully uneducated in the mechanical arts, it was tough to guess what might be wrong—it could have been anything, and frankly they could have told me anything. The cost of ignorance is high.

Luckily, the folks at this particular garage are exceptionally honest. New tires, they said. That's all you need. Dry rot's taken over the old ones. OK, that's a relief, I thought, …sort of. It was nice to know there was nothing wrong with the engine or chassis, but spending money on tires felt deeply unsatisfying, like somehow it was money for nothing. I'd resigned myself to investing in a more fundamental, important upgrade to my car.

These feelings of dispirit vanished as soon as I pulled out of the parking lot, and then quickly morphed into a new series of sensations. I felt excited, renewed, relieved—the car was driving beautifully, perfectly! It did not have mechanical problems. It was not showing signs of age. No, rather, it had a maintenance problem, an ownership problem. The owner did not understand the paramount importance of tires. I was reminded of the reaction I have every time I change my guitar strings. As my strings reach the end of their lives and my tone suffers, thoughts of new guitars, new gear appear more and more often. Then, with a new set on, I think only: Wow. I've got to start doing this way more often.

"I've many times said to someone, ‘You put a set of Martin strings on there, and it'll leap to life,'" world-renowned guitar virtuoso Tommy Emmanuel said when we spoke for this article. "At the moment, it's being held back by bad strings, but there's nothing wrong with your guitar." Had I heard this months ago, I doubt I would have been smart enough to apply his wisdom to my car, but at least I would have spent less time worrying that I needed a new guitar. "The sound of the strings—that's my world," says Tommy, and perhaps this is why he puts on a fresh set before every show. This is probably also why NASCAR crews may change tires up to 12 times during a single race: Top-of-the-line engines and world-class drivers notwithstanding, those tires are key. Meanwhile, many everyday motorists wait for their tires to go bald, and too many guitarists are playing dead strings.

There's a certain devil-may-care attitude about strings that's grown out of some musical cultures, and in some cases there's plenty of good reason for it (like, for example, your string budget being one in the same with your food budget). But "three chords and the truth" sounds a lot snappier than "three chords, a lively set of strings, a proper setup, a thoroughly warmed-up voice, and the truth." The mythologies of our heroes can mislead as much as they inspire.

So, let's set the record straight: Strings are really important. A guitar without strings is, at best, a very expensive drum. The way accomplished players like Tommy Emmanuel, who are highly sensitive to both the sound and feel of their strings, can felicitously describe the defining qualities of a given formula really underscores this point. "When Martin sent me some SP Flexible Core strings, I was thrilled because they still had toughness to them, but they also had that flexibility and a softer feeling even though they were 54 to 12 [gauge]. It's a solid-feeling string, and it just has a sweetness that I really love." However, to really appreciate what makes a player like Tommy Emmanuel gravitate towards a string like the SP Flexible Core, it helps to first have a basic technical understanding of the string itself.

The first thing to know about guitar strings is that there are either one or two basic parts: the core wire and the wrap wire. On the higher B and E strings, the core wire is the guitar string. On the lower E, A, D and G strings, both components make up the string. If the lower E, A, D and G strings were a corndog, that core wire would be the pork/ beef/soy/unknown meat-like product, and the cornmeal would be the wrap wire. This is a slightly imperfect analogy since the wrap wire is, as the name suggests, wrapped around the core wire, but the basic idea remains: There are two parts to these guitar strings, and one lives hidden inside the other. Like a corndog, there exists an ideal ratio between the inside core and the outside layer, or rather there exist a few ideal ratios for players of different tastes.

Martin originally developed the SP Flexible Core strings for beginners, whose tastes are largely dictated by their emergent abilities and still-callousing fingertips. The idea behind the SP Flexible Core string is that you can slenderize the core wire while fattening the wrap wire to produce a string that has the same volume and tone as a traditional string, but is more flexible and has a softer touch. SP Flexible Core strings are easier to bend, which makes them an ideal string for fingerstyle players. This is part of the attraction for pros like Tommy Emmanuel, who also observes that "it's much more accurate with the capo as well. Strings impact everything." Similar to the way Coca-Cola® was originally conceived as a treatment for headaches, but turned out to be more popular as a soft drink, the SP Flexible Core strings were originally designed to complement the needs of beginners, but this innovative string is now valued by a panoply of players for different reasons.

Martin has been manufacturing its own strings since 1970, and 2017 marked the 20th anniversary of the launch of SP core wire, which is the particular type of core wire used in all of the Martin Strings families with "SP" in the name. SP core wire is made from premium, high-tensile steel that holds tuning longer, and the successive insights of the SP Flexible Core strings wouldn't have been possible without these earlier innovations. The SP core wire used in SP Flexible Core strings is the finest, thinnest core wire that's been produced by Martin's manufacturing team.

Despite the foregoing, technical knowledge is not a prerequisite to appreciating the SP Flexible Core strings. As Tommy puts it, "I don't profess to technically know a lot about strings. All I know is what works for me. I live in the real world—I have to get the best sound I possibly can, the best tuning I possibly can, and consistency every time."

They say music's greats make it look easy, but when Tommy Emmanuel picks up a guitar, there's no delusions about the skill behind his music. His alacritous playing is filled with an energy that seems to warp the normal dimensions of time; the listener, rapt in attention, feels weightlessly suspended in the moment of every beautifully articulated note. Tommy's tone is of course no accident either; he carefully considers, and exhaustively experiments, with each component of his sound. But, as an acoustic fingerstyle player, there are only so many elements in the equation, and strings are chief among them. "I've always been very conscious of what strings work. Nowadays, I'm pretty guaranteed that every time I put a set of Martin strings on my guitar, it's not only going to sound great, but it's going to tune up just right—what's important to me is that the guitar feels great, but more importantly, tunes up perfectly." That being said, Tommy's preferences are based on what works rather than brand loyalty, and he'll be the first to tell you that he's open to playing any string—it's whatever sounds good to his very exacting ears.

For Tommy and the SP Flexible Core strings, it was decidedly not love at first touch. The technology took some time to perfect—when you're trailblazing, there is no path to follow, and a few crooked turns are simply part of the journey. "It was probably around 2009 or 2010 when I came up to Canada on a tour, and Martin gave me a bunch of strings to try out. They were looking for feedback on the SP Flexible Core strings. The third string kept breaking, so I mentioned that. They went back and did some adjustments and sent me some more strings, and they were perfect. I said you really got it now!"

Even though the SP Flexible Core is now Tommy's preferred string, his real world concerns demand that he heed his intuition. For example, Tommy has found, "If you use the same string for every string change, after a few weeks of doing that, the real brilliant, complex textures that new strings bring out of the guitar will start to die away. And you'll change the strings, and you'll say they don't sound as good as they normally do." So what does Tommy do to cleanse the palate of his guitar? "Sometimes I'll put on Martin's new Retro™ strings, and they work really well, too. But it's a totally different sound!" Still, the SP Flexible Core remains his go-to string because it sounds great, feels great, and because "I can put on a brand new pair of strings and not check my tuning for five songs, and it'll still be perfect."

Learn more about Tommy's choice, Martin's Flexible Core strings.

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