There’s no denying that changing the action on your classical guitar can have a profound effect on its playability. But did you know that changing the action to be higher or lower can also have a significant impact on the dynamic capability and tone of your guitar?

In this post we will define what the guitar action is, explore it’s effect on your guitar, discuss the pros/cons of a higher or lower action and teach you how to measure and adjust your own classical guitar action if required.

Understanding what the action is on your guitar can be useful in furthering your understanding of how a guitar functions, which has a clear impact on how you shape your technique. It may seem insignificant and is admittedly only a small part of the puzzle, but understanding ‘action’ is helpful nonetheless and should not be entirely overlooked, even if you have no intention of changing the action on your classical guitar.

Action has a profound effect on a guitar’s playability, as the closer the strings are to the frets, the less energy is needed to fret notes by the guitarist.

A low action makes basic fretting much easier than a high action. Less energy is needed to push the string towards the fret. Because the strings are closer to the frets, there is less chance of pushing the string in a diagonal direction (i.e. not perpendicular/90 degrees to the fretboard, essentially ‘bending’ the strings). Reducing diagonal pressure and string bending means it is easier to play with good intonation.

A high action where the distance between the top of the fret and bottom of the string is greater, means more energy is needed to fret a note. A higher action requires greater care to push the strings directly towards the fretboard which some players may find difficult.

Because the distance is greater, the string is bent more during the fretting process which in extreme cases can affect intonation. Whilst the guitar is not a well-tempered instrument in the first place, factors that affect intonation only make matters worse.

So a low action is best, right? Not necessarily. Read on to find out why there is so much debate surrounding the best action for a classical guitar.

You would be forgiven at this point for assuming the lower the action, the better. However action affects more than just playability, it affects the tone and dynamic capability of a guitar as well.

When a guitar’s action is lowered it increases the likelihood of the strings contacting the frets when played. When this happens to a small degree, it will take some energy out of the string and reduce sustain. Notes may also sound less vibrant as they clip the top of the fret. In more extreme circumstances, the string will rapidly and repeatedly hit against the frets and produce a buzzing sound. This is usually when most players notice there is an issue.

The harder or louder the string is played, the worse this effect gets. To offset against the buzzing issue, players will resort to playing more quietly. Whilst this fixes the buzzing issue, it means that the dynamic range of the guitar has effectively been reduced.

Classical guitars do not have a huge dynamic range to begin with, so limiting your dynamic range further makes expressive and musical playing all the more difficult.

A higher action means that the strings can be pushed harder before they contact the frets. This helps to increase the dynamic range of the guitar and make expressive playing much easier. Playing with dynamic contrast is one of the key tools in the classical guitar players arsenal, so it makes sense to ensure your guitar action is set up to allow for this.

Because the strings are not contacting the frets, you may notice an increase in vibrancy and sustain the higher you set the action. These two characteristics enhance the tone of your guitar and allow it to sing to its full potential.

The best action for a classical guitar is essentially a fine balance between playability and intonation vs dynamic range, tone and sustain. It’s simply not possible to have the best of both worlds, so we must be willing to compromise to some degree.

The good news is that there is usually a sweet spot where the player feels their guitar plays well and they are getting a satisfactory level of tone and dynamism from their instrument; the optimal action.

The bad news is that this differs from one guitar to the next, and levels of what is deemed acceptable also differ from one player to the next. So unfortunately, it’s not possible to publish the precise measurement at which you should set your guitars action.

Take a look at the table in Figure 1 containing action measurements on a range of guitars we’ve had in the CGA studio.

As you can see, professional luthiers cannot agree on one single ‘perfect’ guitar action. They take into account the degree of neck relief/profile among other things to work out how to set the action on their guitars. The only thing they all agree on is that the action of the low E string should be higher than the action of the high E string.

The best action for your classical guitar will depend on your own circumstances. In other words, the guitar you play and your own preferences.

So how do you work out the best action for you? The first step is to play your guitar and really listen to the tone. Push the guitar as hard as your technique allows and listen for any buzzes. From experience, I would recommend playing apoyando (rest stroke) when you push the guitar to its limits, as you are less likely to pull the strings away from the body which may result in premature buzzing; a limitation of technique rather than the instrument itself.

When pushing the guitar to its limit (or your own technical limit) do you notice any buzzing? If so, is it minimal or excessive? Excessive buzzing would suggest the action needs to be higher. This means a new saddle and/or a new nut.

If the buzzing is minimal, would you be happy with this as your guitars dynamic ceiling? If yes, you can start thinking about how the guitar feels when you play. If not, you may be better looking to upgrade to a new classical guitar with better projection and dynamic range.

So, let’s say you’re happy with your guitars dynamic range. How does it feel when you play? Do the strings feel comfortable under the fingers. Can you fret notes accurately? Are you avoiding string bends when fretting notes? If all is well, there is nothing to change!

However, if you do have some gripes with comfort, accuracy, unintentional string bending, general clumsiness etc it may be worth exploring a lower action.

Of course, lowering the action will have an effect on the dynamics/tone as we discussed earlier, so use a little common sense to make a judgement as to how much of a change you think you can get away with. Remember that even 0.25mm can change the playability of a guitar significantly.

I should mention at this point that fret buzz may not just be caused by the action. If you own an older guitar, there is a chance that some frets may have unseated themselves slightly. This means that they may be sitting slightly proud rather than flush. You can check this by rocking a straightedge (a credit card will do) over 3 consecutive frets. If the straightedge rocks from side to side, you have an unseated fret. If this is the case, you will need to factor this in when changing the action. Consider having the frets levelled and recrowned first for optimal playability/tone.

Measuring your guitars action is relatively straightforward when you have the right tools. You can acquire a string action gauge relatively inexpensively. Failing that, a ruler where the tip begins at 0 and allows measurements in millimetres.

Place your string action gauge on top of the frets so that the ruler lines up on the 12^th fret. Start with the gauge touching the 6^th string taking care not to bend the string. Take the measurement from the bottom of the string. Repeat the process for the 1^st string.

Congratulations, you have just measured your guitars action.

You can change the action of your classical guitar by making the saddle higher or lower.

If you need to lower the action, slacken/remove the strings, slide out the saddle and sand down the bottom of the saddle to the desired amount. Remember, you can always take more off, but you can’t put it back on! It’s advisable to measure your action first, decide how much you’d like to take off and then mark up the saddle with a pencil and straightedge. Sand on the waste side of the saddle stopping at the pencil mark (rather than sanding into the pencil mark). Fine tune a little further if/as required.

Tip: the saddle is designed to be a snug fit and the pressure of the strings may have made it difficult to remove. Being extremely careful, a short, sharp tap with the edge of your string action gauge may do the trick. Cover the bridge lightly with masking tape, cardboard or another suitable form of protection just in case you slip (finish permitting). Please note, we accept no damage liability for your DIY handywork! Defer to a professional if you don’t feel comfortable doing this.

If you need to higher the saddle it’s possible to use a shim (a thin piece of material than can be placed under the saddle to effectively higher it). Shims are a reasonable solution, however it is advisable to make a new saddle to maintain the best connection between saddle, bridge and soundboard to allow optimal resonance of the strings/soundboard.

It’s perfectly possible to make a new saddle, however this is perhaps a topic for another time as there are some intricacies which extend beyond the scope of this post.

By now you should feel confident in understanding guitar action, how to accurately measure the it and how to adjust it if required. It’s useful to understand how the action of your guitar affects its playability and tone, so you can make informed decisions when it comes to making adjustments or buying a new guitar.

If you’ve pushed your guitar to its limits and you don’t feel satisfied with it’s dynamic range after setting the action to your liking, or perhaps your guitar just doesn’t lend itself to being set up to your preference, it may be time to find a new guitar that suits your needs.

We sell a range of superb classical guitars, all of which have been tried, tested and approved by us personally. Our rule is, if we don’t love it, we don’t sell it.

Get in touch with us today to discuss your needs. We’ll be happy to chat to you in detail and find a guitar that suits you perfectly.