Sometimes a guitar is just inherently dull. But usually, there is a specific reason a guitar might sound dull, and there are things you can investigate to figure out what the cause may be.
In this article we will explore some of the common reasons an acoustic guitar might sound dull, and why an electric guitar might sound dull.
Reasons An Acoustic Guitar Might Sound Dull
The most obvious, and easiest thing to investigate first, when trying to find out why your acoustic guitar is sounding dull, is to look at the guitar strings.
If your strings have been on your guitar for a long time, or there has been a lot of humid weather, this can impact your string vitality, and mean that you need to put new strings on.
Changing strings should always be the first thing you do when trying to improve the sound of your guitar.
Initially put on strings of the same brand and thickness as you always have, but if that does not improve things try lighter gauge strings because these often have more higher-end tones.
Sometimes a new set of strings on its own will make all the difference and the life in your guitar will feel like it has returned.
The action on a guitar refers to the distance between the guitar strings, and the fretboard. if this distance is large this is referred to as high action, and if this distance is very small, this is referred to as low action.
If the action is too low, this can interrupt the normal acoustic processes, and vibration of the strings and make your guitar sound dull.
So in some situations, by increasing the action on your guitar, you can reduce the dull sound.
The guitar nut is a small component that sits at the head end of the guitar neck and all strings sit in the nut, with a slot each that helps them be spaced out correctly and sit above the fretboard at the right height. On cheap guitars, these nuts are made from plastic, whereas on expensive acoustic guitars these nuts can be made of other exotic materials such as bone.
If you have a plastic nut, then you could swap this nut for an ivory nut, and see if this makes a difference.
Many people have found that the material a saddle is made of has a significant impact on the tone of a guitar and whether it sounds dull or not.
The saddle of a guitar sits at the opposite end of the guitar nut. The saddle is a small and thin piece of plastic or ivory (or other material) that sits on the guitar bridge, that also holds the strings up off of the fretboard.
As with the guitar nut, this is commonly made out of plastic (especially on cheaper guitars).
However, when these are made out of plastic this can influence the tone of the guitar and potentially contribute to a dull sound. Sometimes these also develop cracks, which are not obvious from the outside, which can have a big impact on the sound.
So if you cannot eliminate the dull sound of your acoustic guitar, you can try swapping a plastic saddle for a saddle made out of another material (potentially ivory).
The relief of an acoustic guitar refers to the curve of the guitar neck. Guitar necks are designed to be slightly bent, in terms of bowing forwards.
But through either bad configuration or the impact of humidity, sometimes this relief can be impacted, and need an adjustment.
The relief of your neck can be adjusted by making adjustments to your guitar truss rod, which is a metal rod traveling the length of your guitar neck that you can either be tightened, or loosened to adjust the extent of this bow, and the direction in which the bow goes.
If the bow in the guitar neck goes backward, this is definitely not good and you would need to adjust your truss rod to make the bow go in the opposite direction (slightly forward).
But if the bow is already facing forwards, it is a matter of making sure the bow is of the right curve.
If the bow is too strong in the forward direction, then there will be a large distance between the strings and the fretboard which could make it not only sound bad but also harder to play.
Unique Wood Properties
Given that acoustic guitars are made out of wood, and/or laminate, there are occasions when, very randomly, the piece of wood that is used to make a guitar, just has very bad acoustic properties, and sounds inherently dull.
If all of the above adjustments are made and perfected, and your guitar still sounds dull, it could be that the guitar is just a naturally dull-sounding guitar.
If you take your guitar to a guitar technician they should be able to clarify that the setup is correct and that there is nothing further you can do.
In summary, if your acoustic guitar sounds dull, the first thing you should do is change your strings.
If a change in the guitar strings does not have the desired impact, then explore the guitar action and the guitar relief and see if some adjustments to the guitar neck, can improve the sound.
Once the guitar neck is properly adjusted, and you still have a dull sound you can try changing the nut and the saddle of the guitar.
Sometimes swapping these out can improve the sound in the event they are either broken and you didn’t realize, or made of inferior materials that we’re having a negative impact on the sound.
If none of these things made a difference, then it might be worth taking your guitar to a guitar technician.
A technician is likely to look over these same things, but if they can find no problems with the work you have done, and nothing else is wrong, it could just be that the unique properties of this individual guitar you own are that it sounds a little bit dull.
Reasons an Electric Guitar Might Sound Dull
There are some similarities and differences between an acoustic and an electric guitar, in why they might sound dull.
If an electric guitar sounds dull it is good to first try changing the strings, and then checking the string action, and the guitar neck relief as these can make an electric guitar sound doll, as well as an acoustic guitar.
The specific wood that an electric guitar is made out of, is a lot less likely to have an impact on the sound of an electric guitar.
However, many players have noted that guitars with a very thick paint job do have different tonal properties than guitars with a thinner paint job.
It may be very difficult to figure out how thick your guitar paint job is, but if that is something you have personally worked on in recent memory, then that may be the cause of a change in the sound of your electric guitar.
It seems very obvious, but always double-check the position of the various tone control knobs on your electric guitar if you have not already.
Sometimes we get very set in our ways in where we have our knobs set and rarely change them. This is fine for the most part, but if we then accidentally adjust one of these knobs and do not know that we have done so, our guitar may start sounding very different.
Again, that is very low in likelihood, but it is worth checking to rule it out.
Nut & Bridge
The nut of an acoustic guitar is a lot less likely to have an impact on tone than the nut of an acoustic guitar.
However, if you have a tone problem on your electric guitar it is still worth double-checking the nut to make sure it is free from damage and adjusted correctly.
The electric guitar bridge is something you do want to pay close attention to, especially if you have a complex mechanism such as a Floyd Rose Tremolo Bridge.
Make sure the action is adjusted correctly and the strings are sitting inside the bridge properly and at the correct height to eliminate this as a potential source of the dull sound.
This article has covered some of the major reasons that an acoustic guitar might sound dull, or an electric guitar might sound dull.
If none of these ideas have made an impact on the sound of your guitar, and it still sounds dull, then unfortunately it could mean that either your guitar is uniquely dull sounding, it is a dull sounding model, or you need to take it to a guitar technician for further investigation.