Well, I hate to be the bearer of bad news, but your guitar does not play in tune.
The guitar is an imperfect instrument when it comes to tuning.
However, there are a couple of things you can do as a builder and as a player
to help your guitar play as close to in tune as possible.
One is called compensation and is usually done while the guitar is being built.
The other is called intonation and can be done after the guitar is built.
These are pretty complicated subjects. I highly recommend that you do some research
on these subjects so that you know more about them.
Today I am going to talk about the subject of intonation
and show you how to adjust the intonation on your guitar.
So recently I had what is known as a harp guitar come into my shop for some repair work.
This particular harp guitar is based on a Brazilian instrument called a viola caipira.
This particular harp guitar has thirty strings
so if you are going to learn about intonation this is a great way to learn.
There are a lot of strings to intonate.
So, like I said guitars do not play in tune
but we are going to try and make this guitar play as in tune as possible
and the way that we are going to do that is by adjusting the intonation if necessary.
First let me show you how to check the intonation.
Start by making sure that the guitar is in tune. Tune all the strings.
This particular guitar, the ten main strings, or the five double courses are tuned to a D.
So, once you know that the guitar is in tune,
for each string you want to play the harmonic at the 12th fret.
So I am going to start by placing my finger and playing the harmonic.
It is not fretted. It is just touched and plucked and then remove the finger.
So, as I play the harmonic, my tuner should tell me if it is in tune or not, and it is.
There is a D.
The next step to check the intonation is to depress
on the string at the 12th fret, play the actual fretted note.
So, now I am going to play the fretted note and pluck the string.
As I play the fretted note I want to see the exact same note on my tuner and I do.
Now there are several ways to check intonation with your tuner.
You can use a strobe tuner, get real fancy if you want to, drive yourself crazy in a hurry
cause it is never going to play in tune. Just do the best you can.
I just use this little tuner that clips on my peghead there
and it tells me real quick if the note I hear when I play the harmonic
is the same pitch as the note that is the fretted note on the string.
In this case it is. No adjustment needed.
Now let’s talk about what to do if they were not the same note.
If I played the harmonic and then the fretted note went sharp of the harmonic pitch,
then I have got to make some adjustments and here is what I would do.
So, the fretted note is a little bit sharp of the harmonic
so you want to change the length of your scale
and if it is sharp you want to bring the break angle on the saddle back just a skoshe
and that will adjust it so that the fretted note goes a little flat
and should be in tune with the harmonic note.
Since this guitar has two D strings, I need to check them both.
There’s the harmonic. There’s the fretted note.
My tuner says that they are exactly the same pitch.
So, no adjustment needed. So, let’s check the next string.
The next string is an A on this guitar. I will play the harmonic first
and it says it is an A. Now, I am actually going to depress the note
and it is also an A. So, let’s check the next string.
It is strung in unison on this guitar and once again I have an A.
Once again the fretted note is an A but just a hair sharp.
So, if we wanted to we could try and adjust that a little bit.
So, for the string that was going sharp on the fretted note, which was this one here,
what I am going to do is come In and move the string out of the way
and file the break angle so that it comes back just a skoshe.
I therefore am increasing the scale length just a little bit.
Then place the string back on there.
Just that little bit should be enough to do it. Let’s see if it did.
Ok, so here is the harmonic on that string and here’s the fretted note.
And they are exactly the same.
So, those strings have been intonated.
I have done the first four strings, the double courses which are in unison here
and intonated those strings. Now I have to do the rest.
So, this is very good practice for intonating a guitar.
Six string guitars are much easier.
So, what I have just shown you is a very simplistic way of adjusting intonation.
It is much more in depth than what I am able to present here in this small video.
So, do your research. So, here is another quick little when you are adjusting intonation.
The human ear will pick up a sharp much quicker than it will pick up a flat.
So, if by chance you happen to set everything up just a skoshe on the flat side,
as you play up the neck of the guitar, bending the strings, stretching them,
it should come right in to about what our ear thinks it is in tune.
So, there you have it, a quick and easy way to adjust intonation on your guitar.
Now I have got to get busy with the rest of those strings.