Overtones and undertones in guitar sound

Short Summary

Every note you play on a guitar consists of a fundamental frequency—the main, identifiable pitch—accompanied by higher secondary frequencies known as overtones. These overtones shape your instrument’s unique timbre (sound quality) and allow you to intentionally play artificial or natural harmonics at specific frets. Interestingly, guitars do not actually produce true undertones because a sound wave’s wavelength cannot exceed twice the physical length of the string. Beyond your guitar’s build, external factors like your tuner pedal placement and even the thickness and material of your guitar pick directly influence how these complex overtones interact, heavily dictating your final signature tone

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What are overtones and undertones in guitar sound?

If you play the note A on the high E-string (5th fret) on your guitar, this A would be (depending on tuning) 440 Hz.
This is called the main pitch frequency. It’s the easiest to recognize in the sound.
Also known as the fundamental frequency.

Besides this frequency, your guitar will produce many other frequencies, some of which will be higher (overtones).
This happens because besides the vibration of your string, you get the vibration of the instrument and vibrations of your string that you do not necessarily expect. In this case you might want to know more about the scale length of your specific guitar.

An overtone / undertone is a frequency in a sound that is different from the fundamental frequency.

Frequencies of guitar tone

We already know that the main pitch frequency of “A” is 440 Hz on a guitar.
That means one octave lower (G-string 2nd fret) the frequency is 220 Hz and the open A-string is 110 Hz.
Actually we are talking upside-down according to the schematic diagram below.
The 1/3 wave of the A-string can be found on the 7th position. Fretted this would be the note “E”.
According to the already mentioned frequencies within the A-string, 330 Hz is a logical result.
About this 330 Hz, more at “How to tune your guitar right” below.

Fundamental frequency

The fundamental frequency is the main frequency of the note. It is the most pronounced frequency in the instrument or vocal sound.

Overtones also known as “partial waves”

Overtones are important because they change the quality of the sound (the timbre of the sound) produced.
These overtones and (sometimes) undertones are the reason why different instruments sound differently even when they are playing the same note.

These tones are sometimes more pronounced, such as with brass instruments and toms, and sometimes less. Certain instruments produce overtones / undertones that are always present, called formants.
Formants are essential for the timbre of the instrument.

Formants

A formant is a frequency that an instrument or a voice always produces, independently of what note the instrument is playing.
Formants are important as their presence determines the timbre (the qualities) of the sound produced by an instrument.

Harmonic overtones

Certain instruments produce harmonics, which are nicely sounding overtones. An overtone or undertone does not have to be harmonic. Though it could be an inharmonic overtone as well.
Harmonic overtones are the frequencies of which are an integer multiple of the fundamental frequency.
For example: the harmonic overtones of “A” (440 Hz) are 880 Hz, 1320 Hz, 1760 Hz and so on.

Inharmonic overtones

Also known as “partial overtones” or “partial harmonics”, are overtones that are not an integer multiple of the fundamental frequency.
Digging deeper into inharmonic overtones may become very difficult and we advice you to check explanations on the internet.

How to tune your guitar right

Now we are talking about harmonics for guitar, this is where it becomes interesting.
As you know, an open A-string on guitar is 110 Hz.
So playing a harmonic on the 12^th position on the same A-string, which is half of the string, must be 220 Hz.
This is still the fundamental A-note.

Beware of tuning your guitar with the use of just harmonics

E-string harmonics
The frequency of the low E-string is 82 Hz, so the harmonic overtones for E are 82 Hz, 164 Hz, 246 Hz, 328 Hz and so on.
Harmonics played on the 5th fret on the E-string is 328Hz.

A-string harmonics
A harmonic on the A-string (7^th fret) will produce 330 Hz (see schematic diagram). This is because it is part of the harmonics on the A-string.

So using both harmonics on the E- and A-string officially means there is a gap of 2 Hz.
In the first diagram you will see the * with = 330 Hz, which is because we don’t want to call this “E = 330 Hz“

Why won’t my guitar stay in tune?

Well, that is a problem for a lot of people. 10 reasons why your guitar does not stay in tune to help you with this problem.

Nobody will hear a difference of 2 Hz

Of course, the difference mentioned absolutely is negligible, so you won’t have a problem tuning your guitar this way.
But officially it is wrong.

Best way for tuning a guitar

• Use a proper tuner for guitar. Many different brands make great tuners.
• You might also find good online guitar tuners.
• Play the harmonic on the 12^th position, for example on the E-string and hit the E on the A-string at the 7^th position (no harmonic in this case).

Tuner pedal place in the effects chain

The best place for a tuner pedal definitely is first in the signal chain. Most important reason for this is that you don’t want any interference from other pedals that may alter the tuning signal in any way.
That said, the guitar effects pedal order on your pedalboard is important for creating the sound you like most.
Read our blog about “the right pedal order”.

No undertones in a guitar tone?

Right, a sound wave cannot have a wavelength longer than twice the length of the string.
When you press down on a fret, you are determining the length of the string. The string will then vibrate in time at multiple frequencies corresponding to higher harmonics.

However, when you pluck a harmonic like on the 12th fret, you have some contribution from the open string vibration since you are not technically holding the string fixed.

Which frets are best for you

The right frets are very important for your style of playing. Learn more which frets are best for you in our special we wrote for you.

What is the difference between overtone and the pitch?

An overtone is any resonant frequency above the fundamental frequency of a sound. An overtone may or may not be a harmonic.
In other words, overtones are all pitches higher than the lowest pitch/fundamental within an individual tone.
It is called the string’s fundamental, or first harmonic.

That said, it doesn’t matter whether you are using humbuckers or single coil pickups or using digital- or analog amps-/speaker cabinets as well.

Overtone in relation to octave

The string also vibrates in halves, producing a sound with twice the frequency (number of vibrations per second) of the fundamental. This tone—an octave above the fundamental—is called the first overtone, or second harmonic.

Are harmonics the same as overtones?

“Overtone” is any higher-frequency standing waves.
“Harmonic” is used for all integral multiples of the frequency of the fundamental.
Both overtone and harmonic are called resonances.

The Role of Overtones:

1. Timbre: The specific mixture of overtones gives each instrument its unique sound or timbre. The guitar’s distinctive sound is largely due to its overtone structure.
2. Harmonics: Guitarists can play specific overtones called harmonics by lightly touching the string at certain points, like the 12th, 7th, or 5th frets, and plucking the string. This action suppresses the fundamental tone and allows only the overtone to sound.
3. Chord Resonance: When playing chords, the interaction of overtones from multiple strings can create complex sounds and contribute to the overall resonance of the chord, along the resonance of the guitar body and neck itself.

Understanding overtones helps guitarists to better control the sound of their instrument, whether they are aiming for a warm, mellow tone or a bright, resonant sound.

Timbre, Harmonics, Overtones and wave shapes

All sound is generated by vibrations. When objects vibrate repetitively and predictably our ears interpret the resulting pressure waves as tones or pitches – the sort of thing you could play a tune with.
Objects which vibrate in non-periodic and random ways generate waves which we interpret as being noisy or atonal.

Timbre is the quality of a sound that is distinct from pitch and intensity.
Different patterns of vibration produce sounds with different timbres.

In other words, a flute and a violin may play the same note, but the quality of the sound produced by each instrument is markedly different. The timbre of a sound is determined by the presence or absence of overtones and/or harmonics.

Pick noise may also affect your tone

The material of your guitar pick is made of and the way you hit your strings may cause overtones and/or harmonics. This means that your guitar pick has an influence on your tone.

Make your guitar sound better with the tips in this blog about guitar tone and use the right microphone technique when you need to amplify your guitar amp.

Thick guitar picks will help you achieving the guitar tone you are looking for.

Best guitar picks for beginners

When you’re new to guitar, you might want to know what is the best guitar pick for beginners;
In another blog we wrote, you may find all things that are interesting for starters and especially which ones are the best guitar picks for beginners.

Better grip using pick grippers

Regardless the brand or shape of the pick, it remains important that your pick stays stable and does not slip or turn between your fingers. Gripperzz are specially designed for the best grip on your guitar pick. Gripperzz are small soft rubber grip stickers in the shape of a guitar pick.

3 basic types of sound

In digital terms, we often talk about 3 basic types of sound wave.

• The sine wave is a pure tone with no overtones.
• A square wave is composed of a fundamental and odd harmonic of the fundamental.
• A saw wave is composed of a fundamental and all harmonics of the fundamental. The fundamental is usually the loudest component of the signal, and the harmonics decrease in loudness as they increase in frequency.

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What others say about ChickenPicks guitar picks

Musikhaus Thomann
Chicago Music Exchange
Guitarpickreviews.com
Anatomy of guitar tone

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F.A.Q.

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Guitar essentials

In guitar essentials we write about interesting things every guitarist should know a bit of, especially when you’re new to (electric) guitar.
We definitely don’t dig deep into theories or technical aspects.
You will find many scientific documents about anything somewhere on the internet.