Why are the frets on a guitar not evenly spaced?

[TJE"]

Sorry if this is a silly question - but would this not make it easier to play? or is there some kind of physical law that makes it impossible?

[SongwriterFan]

Physics.

If the frets were equally spaced, the notes wouldn't be the ones in our 12-note scale.

[devellis]

The frets are located so that they correspond to the locations where the strings will be in tune when pressed against them. If they were spaced at equal intervals, fretting consecutive frets would give you notes that were out of tune.

[RP]

Because for a string instrument, notes have a multiplicative, not an additive relationship...

[ljguitar]

Originally Posted by TJE"

Sorry if this is a silly question - but would this not make it easier to play? or is there some kind of physical law that makes it impossible?

Hi TJE

Great question. They are not evenly spaced (for reasons already "noted"), but they are very precisely calculated and spaced mathematically. It's not for aesthetic purposes.

From the "Build Your Guitar" website:
Calculating fret distances.

If you divide any scale length by the constant 17.817, you will get the distance from the front edge of the nut to the first fret.

Here is one example: a scale length of 25.5" (650mm) divided by 17.817 gives 1.4312173" (36.482011mm), which can be rounded down to 1.431" (36.48mm).

All fret distances should ideally be measured from the front side of the nut or a potential zero-fret, as otherwise several minor errors in the actual fretting could eventually add up to quite considerable differences.

It is consequently advisable to determine all fret positions by measuring from the nut: the first fret is placed at a distance of 1.431" from the nut, the second at 1.431" + 1.351" (=2.782") from the nut, and so on.

For calculating the position of the third fret, the remaining scale length - i.e. the distance from the second fret to the bridge - is again divided by 17.817, and so on for all other frets. For the 12th fret the calculations have to give exactly half of the total scale length

Glad builders are following the math properly. I prefer to play the right notes, and play them in tune.

[TomB'sox]

Originally Posted by ljguitar

Hi TJE

Great question. They are not evenly spaced (for reasons already "noted"), but they are very precisely calculated and spaced mathematically. It's not for aesthetic purposes.



Glad builders are following the math properly. I prefer to play the right notes, and play them in tune.

They make a big point of measuring from the front of the nut and are down to the thousand of an inch, but where are they measuring on the fret itself, the back edge, the middle, or the front?

[rick-slo]

Originally Posted by TomB'sox

They make a big point of measuring from the front of the nut and are down to the thousand of an inch, but where are they measuring on the fret itself, the back edge, the middle, or the front?

The middle of the crown.

[TomB'sox]

Originally Posted by rick-slo

The middle of the crown.

Gotcha, thanks.

[ruby50]

Then what the heck is this?

http://www.freenotemusic.com/site/store/guitars.html

Ed

[Denny B]

Originally Posted by ruby50

Then what the heck is this?

http://www.freenotemusic.com/site/store/guitars.html

Ed

The equivalent of using a shotgun to swat a fly?

[Earl49]

Originally Posted by ruby50

Then what the heck is this?

Simple really. This is a microtonal neck. Standard guitar necks are for the traditional western scale of twelve half-steps or semi-tones per octave. Those extra frets give you notes in between those twelve half steps. Micro tonal music is typically of Asian, Indian, or African origins.

You can get the in-between notes on any guitar using a slide, or by bending. The extra frets let you get there more precisely and reliably.

[dwasifar]

Originally Posted by ruby50

Then what the heck is this?

http://www.freenotemusic.com/site/store/guitars.html

A reason to drink.

[DetroitDave]

Originally Posted by dwasifar

A reason to drink.

Not that we needed a reason in the first place ...

[DenverSteve]

Originally Posted by ljguitar

[size=2]Hi TJE, Great question. They are not evenly spaced (for reasons already "noted"), but they are very precisely calculated and spaced mathematically.

Expanding on what Larry said. Here you go. Pretty simple math.

Calculating fret distances. If you divide any scale length by the constant 17.817, you will get the distance from the front edge of the nut to the first fret. Here is one example: a scale length of 25.5" (650mm) divided by 17.817 gives 1.4312173" (36.482011mm), which can be rounded down to 1.431" (36.48mm).

Well I was going to paste it here but it was too jumbled. You can read it here:

https://educationcloset.com/2017/05/...-nothing-fret/

[robj144]

To be even more precise, in order for music to be easily transposed, the modern tempered scale was invented. In order to match it closely to the natural scale of 7 notes, 5 notes were introduced (sharps and flats) so that the ratio between each successive notes was fixed. Mathematically, to form the octave, the ratio between two successive notes has to be 2^(1/12) (2^12/12 = 2, which is the octave). This is pretty close to the natural scale. For instance, a perfect fifth in the natural scale is a ratio of 3/2 = 1.50, where in the tempered scale, it's 2^(7/12) = 1.498. So, this is the reason why the tempered scale is a compromise, and notes always sound a bit "off' on any instrument which uses the tempered scale.

Now, from physics, the fundamental frequency of a string (for the same string) is a constant divided by the vibrating length of the string:

f = c/L.

Hence, the ratio of the frequency of f1 and the next note, f2, is:

f2/f1 = L2/L1

Which must equal 2^(1/12):

L2/L1 = 2^(1/12)

So,

L2 = L1 2^(1/12)

Hence, every successive note must 2^(1/12) closer to the nut as the previous fret.