Guitar strings are grouped by tension values: light, medium and high tension. Tension depends on three things: scale length, pitch and thickness of the string. Since the scale length of your guitar is a given and the pitch of a specific string is also a given, the only thing that really affects tension in a practical way is the string thickness.
Popularly referred to as ‘gauge’ in the acoustic/electric world, string thickness is simply the diameter of the string. Thicker strings increase tension. Thinner strings decrease tension.
Or to put it another way: if you have a string of a certain diameter and want to achieve a certain pitch at a certain scale length, you need a force to make it happen. That force is tension.
Why would you choose high tension strings for your guitar over normal tension strings or vice versa? High tension classical guitar strings are louder and have a tighter vibration. They generate more partials for a complex sound that players of more modern repertoire prefer. Medium and light tension strings vibrate more loosely when played. They produce a clearer fundamental note with clean sounding chords and harmonies that players of a more conventional repertoire prefer.
We will take up the much-discussed issue of the loudness of high tension strings shortly in more detail. We will also discuss the other important aspect of choosing one type over the other: its playability.
But before we get to that, we must start by observing that there is currently no industry standard of numerical values that conclusively decide if a string is low, medium or high tension. We allow each manufacturer to tell us their considered opinion and we react the best we can.
Let’s look at some numbers
Take a popular set of strings like the D’Addario EJ46 Hard Tension. The low E string (6th string) has a string gauge of 0.0285” at a tension of 15.8 lbs.
Now compare it with the low E string from D’Addario’s EJ44 Extra Hard Tension set. The string gauge is 0.029” at a tension of 16.4 lbs. You can see the extra hard tension string needs to be put under a greater force to generate the same note, the low E.
While it is instructive to look at the numbers behind the different tensions of string of the same manufacturer, the picture gets muddy and inconclusive when you compare tensions between manufacturers.
For instance, let’s take the first string alone of High Tension sets from some popular brands and compare their specs.
High Tension first string
|D’Addario EJ46 HT
|La Bella 2001
If we add more brands to the list above (of only their first string HT variant) you may as a layperson conclude that the diameter range is not that wide after all. But you will certainly notice the tension numbers ‘jumping about’ as they please.
Let’s look at the first string alone once again, but this time of Medium Tension strings from the same popular brands.
Medium Tension first string
|La Bella 2001 MT
The only heartening thing in all this is that the diameter differences between brands are so marginal that you should be able to get any MT string from any brand through the holes in your tie block. Small mercies.
The other value, that of tension, ideally could have been of great practical value but unfortunately isn’t. More so if you consider that some brands don’t stick to the 3 tension types but have extra options like Medium-Hard Tension, Extra Hard Tension and others. Hannabach alone offers 5 tension variants.
Broadly speaking, European makes like Savarez and Hannbach lean towards greater tension than US counterparts like D’Addario and La Bella. And if you’re coming over from the acoustic world, classical guitar strings are of much lower tension than steel strings by the way.
In our quest to decide on the right string tension for our guitar, if facts and specs can’t get us there, talking about ‘feel’ just might.
High Tension strings and playability
The simple act of playing different tensions of string brings to light some noticeable differences. High tension strings feel “tighter” to play when fully tuned. They feel more rigid to the touch than medium and light tension strings.
Higher tension strings are physically harder to press down against the fretboard than lower tension strings. So if you have weak hands or you are a beginner, a lower tension string will work well for you. Although if you are a ‘heavy-handed’ player, as some of us are, know that on low tension strings you will cause buzzing.
Even though High Tension strings are harder to press than Low Tension strings, you may not notice this extra effort when you play. You will probably find your hands getting tired faster. On the other hand, persisting with High Tension strings can strengthen your left hand and also give you a higher volume.
Higher volume. We now arrive at the much-touted benefit of high tension strings.
High Tension strings and greater volume
It’s a widely held idea that harder tension strings produce more resonant notes. A brighter, thinner sound according to some, but the volume gain is evident to most people who try them.
Low or medium tension strings have a slower attack rate than high tension strings. The fast attack rate of high tension strings makes them sound more lively, exciting and complex.
Many players believe high tension strings are perfect for music in the traditional Spanish or Latin mold. The partials in the harmonic series are more prominent and louder. For fast runs and modern pieces as well as flamenco music, the extroverted sounds from high tension strings are a good match.
By this train of thought, playing classical era music or even Bach with high tension strings is considered less than ideal because the fundamental tone is subdued or muddied under all the complexity of the loud partials.
Low or medium tension strings produce a clear fundamental tone. Chords and harmonies sound ‘purer’. Making these strings perfect for good old classical guitar music.
There are folks who prefer a string choice like Hannabach Super Low Tension for this very reason. Older music just sounds perfect. And the low action (easy playability) that goes with low tension is also something some players will prefer.
Your guitar will sound more open with more sustain on low or medium tension. Occasionally, you will hanker after the tighter feel of high tension strings with its added volume. Crossover players often prefer higher tension for the slightly increased volume. High tension strings are also forgiving of a more aggressive touch. They will not buzz.
High Tension strings and your guitar bracing
There are reasons why quick conclusions about playability and volume don’t always work out in practice. One major reason is, on a classical guitar, the proper string tension is dictated by the bracing under the top wood.
Bracing is a complex subject but suffice to say there are many variations in bracing patterns over the decades. If your guitar top is lightly braced like many handmade guitars, low tension might give you the best sound and volume because it takes less energy to get the top moving. High tension strings may pull at the top too hard.
On the other hand, if your guitar top is braced heavily, low tension may not have enough energy to move the top. You will need high tension to get things moving.
In general, factory-built guitars are over braced for durability. So, many will find higher tension strings sound better and have more volume on such guitars. Although there are many other variables (besides bracing) that determine if your HT strings generate great volume or not. If want to learn more about how your guitar’s action affects the sound, read my article How High Should Your Action Be?
The point to note here is that because of such variables, including bracing, you may end up with low tension or medium tension or high tension or any other variant, depending upon how your guitar reacts to the strings.
We are now in a position to finally the answer the question: How do you decide what tension is right for you?
Experiment, experiment, experiment…
Because there are so many variants of tension in the market out there…
Because there is no industry standard with clear-cut implications…
Because it’s not just the thickness or tension that determines how a string will sound on your guitar…
Because the top bracing is a major factor affecting string tension and sound…
You must try as many brands/tensions to see what sounds best on your guitar. Scour the net and you will find a lot of opinions about various tensions, especially in forums like Quora, Reddit and Delcamp. These opinions will prepare you for what to expect and are a good starting point.
Some voices from the www (paraphrased):
I usually prefer low tension strings, but I sometimes also use high tension. Low tension sounds romantic… and high tension strings have a modern character.
I like medium tension strings, they are easier on my hands. Once in a while, I will put on Augustine Blue Regals HT for a change.
If there are a lot of harmonics in a song, they are harder to find on low tension strings and don’t come out as well as on high tension strings. Love the La Bella HT for that.
My strings of choice is D’Addario EJ45. Standard and usual… but they last a long time and very consistent.
My own recommendation is to start your experimentation with variants of the same brand. A good solid set like D’Addario Pro Arte is a great start. Get used to its sound as a base standard for your guitar. Then skip a step and go from, let’s say, light to hard (skipping medium). Or go from medium to extra hard (skipping hard). You will hear the differences better because the tensions are significantly different.
To help you hear the differences clearly, change (initially) only one string, say, the first string. You can listen to it in the context of your other, earlier strings.
With patience and some good, ol’ spirit of adventure, you will arrive at your preferred tension. And it won’t be because you read up some magic formula somewhere on the net. You figured it out yourself.
To explore the world of high tension strings, I encourage you to read my article Why Use High Tension Strings? for insights and guidance. I also have articles on famous and popular brands of classical guitar strings which will help you understand what these offer you by way of tensions and what to try out: Aquila strings review | Hannabach strings review | Augustine strings review.
I have expanded on the subject of experimenting with different brands to find your perfect set of strings in my article 5-Step Guide To Find Your Classical Guitar Strings. You will find it useful if you need a practical starting point. To find out what today’s professional players recommend by way of tips, see our interview with concert guitarist Colin Davin.