Shatter the myth: Heavier strings are harder to play

Dec. 4 2020 - Bryan Lee Peterson

There’s a story that goes something like this: Billy Gibbons and B.B. King are hanging around, and B.B. plays Billy’s guitar, turns to him and says, “Man, you’re working too hard.” He says he plays .08s. Billy takes a minute and thinks about this and decides to go one better and play .07s.

I’m not saying it didn’t happen, but the science and thinking behind it to me is questionable at best.

The Lightest string I’ve ever heard of was a .04 gauge that went on a 12 string bass which had a wider range than a grand piano. The player, Gary Goodman, said that if he looked at it wrong it would break. He is a touchstyle player that relies to a certain extent on light strings, and a lot of fast players are known for their .08s, so maybe there's something to the idea that lighter strings are "easier" to play, but you know this column is about rethinking everything. 

I came out of being a bass player into being a guitarist in my current band. Basically this means I’m a little hamfisted on guitar and I’m learning to be lighter. I knew .09s were too light for me, and I’d occasionally play in a drop D, so 10 through 52 was my string of choice. When I played lighter strings, I’d bend the string out of tune I’d push down so hard.

Earlier this year, I bought an old Ibanez Artist on a late evening from Craigslist, and the guy was a downtuner. I measured it out, and he had the .011 to .056 set on it. I didn’t have anything laying around, but wanted to play it, so I just tuned it up to standard. Turns out, I love this gauge.

I’ve set up the guitar with a good straight setup, and it plays like nothing else to me. I have become a lighter hand with time, and have picked up some speed. I almost feel good enough for my band at this point.

But here’s the thing: I hand this guitar to some shredders and they don’t really notice the heavy gauge. They generally play just about as fast and with just as few mistakes as their own guitar.

So what gives?

Well, let's physics it out a bit. You instinctually think more force is going to be required with a heavy string, and so it’s going to be more work to play, but this isn’t the equation. Work doesn’t equal  simply the application of force, it equals force times distance, right? The amount of force required to tune those strings to pitch is significantly different between the 9 and the heavy bottom 11 set, but this force is transverse to your pressure and doesn’t affect the downward force required for the string to sound. When that distance, your action, is very small, the actual amount of work you have to do to play a note doesn’t change much with more tension.

There’s a legend that Stevie Ray played .013 to .058 strings on his guitar. It seems to be partly confirmed by his guitar tech, but they would shift to lighter strings later in the tours to accommodate finger tendinitis. Part of the legend is that he had a high action as well. Stevie worked for every note he played.

This means we have an example where high action caused some physical difficulty. This is another data point.

So let’s calculate this out. The units used to measure work are designed for much larger amounts of work, i.e., the Newton, which is accelerating one kilogram at 1 meter per second squared. We’re talking more on the level of pushing maybe a gram or two of force by part of a millimeter. So already our unit of measurement would be more than 1,000,000 times smaller than 1 Newton.

We should also recognize that pushing a spring under tension is a little different than pushing a weight along, the further you push it, the more it resists in a logarithmic scale. Doubling the distance may be squaring or cubing the force required, and also increases as you get closer to the end point, the physics of which, I’m sure we’ll get into at some point.

My action is about .75mm at the 7^th fret, or about 45 thousandths (.045in). On the low E, let’s call our equivalent to Newtons a Stevie. If a .038 is 1 Stevie and it increments by .2 per common string gauge, we get to 1.2 stevies for a .042, 1.4 stevies for a .046, and so on. And then we’ll double the distance. Here’s the chart we get: 

*smm = stevie millimeters 

But when we factor in the added tension of the spring resistance, it becomes a very different chart. Let’s assume the force it takes to sound a note squares as we push twice the distance. This becomes a very different chart.

I know we’ve simplified units and made some conjectures, but this is an exercise in seeing how the numbers behave, the height is a very significant factor to consider in determining how much work playing a particular gauge takes. An actual physicist will likely set me right, or maybe if you want to actually conduct the experiment with me I’d be happy to revisit this post, and I have a few physics friends, maybe I’ll get one over post-COVID to set up the experiment.

But there is a different kind of work that maybe we should consider. When I come to a guitar that has .09s or lighter on, I have a different kind of work problem to contend with. I have to work to not push them out of tune, not overbend, and not wrap them around the edge of the neck accidentally if I’m moving fast and playing a little sloppy. I get tendonitis in my hand from this kind of work because of the continuous tension I have to use in keeping myself under control.

I’ll add something into the physics of string vibration as well. Let’s consider a low E string, a .042 string tuned to low E, struck with a certain amount of force will have a wider amplitude than a heavier gauge. The extra tension serves as a constraint on how far off the resting position the string can travel, and this travel happens in three dimensions. When we look down at a string and see it oscillating between high wave points parallel to the fretboard, we don't always realize the same happens perpendicular to the fretboard. This means I can pick my .056 gauge low E harder and not have buzz at a lower action. I have to work harder to contain my pick attack at a lighter gauge.

In multiple ways, I have to work far harder to play light strings with the precision the music I play requires. You might be a heavy strummer singer songwriter type where you hit the strings hard and the get no string against the fretboard clatter, you'd need higher action necessitating lighter strings. This is why guitar setups can be a highly individualized calibration. 

So my answer is really, think about it right. Consider what you mean by working "harder" when you talk about string gauge and tension. If you’re thinking your guitar is too much work to play, your strings are not the only factor to consider. Maybe you just need a setup with lower action.