Sometimes when you’re playing your guitar, it feels like everything just clicks. Your strings, frets, fingers all come together for an instinctive and natural play, and the music just flows.
It doesn’t always work that easily, but when it does, things just feel right. But you’ll never get properly in the zone if your string action isn’t accurate.
Action on an acoustic guitar refers to the space between the underside of the string and the top of the fret.
When string action is correct, you don’t even notice it. But when string action is wrong, things just don’t sound right.
Action can be fixed, and it can be fixed at home. Learning how to lower and adjust your string action can revolutionize how you play, as different actions work with different styles.
In this guide, we’ll discuss how to lower your action on an acoustic guitar, and why you might want to do it.
Why Do You Need To Lower Action On An Acoustic Guitar?
The first thing to note is that there’s no set level of action that’s considered right. How you want your action will depend on your guitar and your style of play.
Higher action is often preferred by heavy hitters, as it reduces the possibility of fret buzz. Lower action is preferred for lighter strummers.
Before You Start
Before you go right in with lowering the action, there are a few things to consider.
First, are these the strings you want?
If you plan on switching to different strings (not just newer, but different), do that before you adjust action.
Otherwise, what worked for your old strings might not be right for your new ones.
Next, give the guitar a play.
Try adjusting your playing style to see what works best with your current string action. It might be that adjusting your style of play is the easier fix for an issue such as fret buzz.
Then, measure the string action. You can do this using a string gauge. Measure at the first fret, the sixth fret, and the twelfth fret, and make sure to measure under each string.
These measurements will help you determine how much to lower the action.
Also, remember that this is advice for acoustic guitars. If you have an electro-acoustic guitar, these methods might cause damage, so you might prefer to leave it to a professional.
Adjust The Truss Rod
The truss rod is a metal rod found in the neck that provides some reinforcement and can be used to alter the straightness.
Acoustic guitar necks shouldn’t be completely straight.
Instead, they should have a slight dip at the center of the neck. If the neck is completely straight, this can lead to fret buzz. A slight hump is even worse.
This is known as back bow, and it will cause fuzz.
That said, too big a dip is a problem. If you’re looking to lower your action, you want to counteract a larger bend. We do this by adjusting the truss rod.
The truss rod will need to be turned clockwise using an Allen wrench, to straighten up the neck. Go slowly, only turning in small increments at a time.
You don’t want to force the truss rod, as this will only cause bigger problems. Turning counterclockwise will lower the neck, raising the action.
Remember that the bigger adjustment is happening at the center of the neck. For every 2 mm at the fifth fret, the twelfth fret is adjusted by 1 mm.
When you think you’re happy with your adjustment, give it a play to see how it sounds.
Adjusting The Bridge Saddle
Our next step is adjusting the saddle. This step is why adjusting the action on an acoustic guitar is harder than on an electric guitar.
Electric guitars typically come with built-in saddle adjustments, while acoustic guitar saddles have to be altered manually.
Begin by removing the saddle. It should either lift straight out, or come away with a gentle pull using a pair of pliers. Check for shims left in the saddle slot.
If there are any, remove them, and put the saddle back. You might find this is enough of an adjustment.
Mark on the saddle how much you want to remove. Use dots to mark how much will be sanded away at the base and treble side, and connect the line.
We recommend sanding from the bottom. If you’re doing this at home, use sandpaper or a sanding block to slowly adjust the saddle.
You might want to practice on a spare saddle before you start. Otherwise, this might be the time to contact a professional.
When the saddle is at your desired height, simply slot it back into place.
If you want to raise the saddle, you can do so by creating a shim from a piece of paper or card.
Sanding The Nut
Finally, you might want to sand the nut. This might not be necessary, depending on how well the neck and saddle adjustments went.
Sanding the nut is a tedious process, as you have to remove the strings, sand, replace, remove, and so on, until it’s right.
To lower the action, you want to file the string slots. You may also need to file the top of the nut, so the strings don’t sit too deep.
When you’re happy with it, string the guitar back to pitch, and see how it plays.
The nut can also be shimmed, if you want to raise the action.
Lowering the action on an acoustic guitar isn’t a particularly easy process, and getting it wrong can be a big issue.
By following these methods, you can do it at home.
The key is to take things slowly, and check and recheck to make sure you haven’t lowered it too far. A little goes a long way when it comes to the action.
Even a millimeter adjustment to the action can affect playability. But get it right, and you can transform your guitar.