View Full Version : Intonation (?)

Bongo Boy
05-23-2002, 05:27 AM
I've tuned up using a tuner, and with each string tuned as perfectly as I can, I go to the 12th fret and check again. Three strings were flat (2 just perceptibly), one was dead on, two were just slightly sharp.

Not that it makes any difference for me as a beginner, but if I could correct this it would be fun. When I go up an octave on a string and it's flat, it seems I should adjust the bridge toward the nut (to shorten the string), then retune the open string, then try the 12th again.

Is that correct? Oh, and is this whole thing related to the meaning of guitar "intonation", or is that something totally different?

05-23-2002, 09:25 AM
Hi Bongo Boy,

No guitar is absolutely perfect and this fact surely sucks :( What really matters is the degree of sound deviation produced by incorrect positioning of frets on a fret board.

!!! And it DOES make difference especially for beginner as your perception of the right pitch is being formed at any time while you play your instrument !!!

I don't think that adjusting the bridge would be of any use cos in any case picking the pitch at the 12th fret is relative to the open string sound frequency. And if your 12th fret doesn't divide your string length into exactly two equal parts the sound will be as bad.

I've got the same problem with my accoustic guitar. As a rule (not with my guitar only) tuner is not enough to make your instrument sound well. It's just a starting point! Afterwards you need to play several chords all along the fret board to adjust the strings tension in a way to get acceptable results in every single case so that you don't need to worry about possible surprises.

And I wouldn't call it "intonation". It's rather a guitar defect. Though I admit it may sound charming along with it :)

Ultra mega best regards,

05-23-2002, 02:08 PM

thats a good answer you gave there.
I just would like to add something: Even though it is true that it is nearly impossible to have a guitar ( especially acoustic guitars ) in tune all over the fretboard, for electric guitars the Buzz Feiten System brings some improvement.
It actually does work, and especially when you combine a "normal" electric guitar with one equipped with a BF-system, you can get some extremely interesting results... Joe Satriani used that effect in the song "Love Thing" ( from "Crystal Planet" )

There are several stock guitars equipped with that system now, i.e. the Paul Stanley-signature model, and Frank Gambaleīs signature model.
Just thought Iīd add...
Warm regards

Bongo Boy
05-23-2002, 02:32 PM
Originally posted by Zatz
I don't think that adjusting the bridge would be of any use cos in any case picking the pitch at the 12th fret is relative to the open string sound frequency. And if your 12th fret doesn't divide your string length into exactly two equal parts the sound will be as bad.

That's why I thought you'd move the bridge--so the fret DOES divide the string properly. [The bridge is one of those that's individually adjustable for each string--"Easy-Tune" or something like that.] Pictorially:

Before Adjusting:

nut------------------------ fret-------------------------- bridge


After Adjusting:


(Way exagerrated, of course, the individual string bridge can only be moved a total of about 8mm without resorting to moving the entire bridge assembly). Is this logical?

I DO understand your point however: even if this works for fret 12, it's only a correction for one symptom and not necessarily for the overall behavior of the instrument.

Bongo Boy
05-23-2002, 02:49 PM
Just read an article that may be worth a read--at least for novices such as myself:


What a great explanation--makes perfect sense to me. A perfectly tuned string, when held down to say the 1st, 2nd or 3rd frets, will have a significantly higher added tension in it than when that same string is held down to, say, frets between 10 and 14.

The Buzz Feiten System doesn't change that fact, but partially compensates for it (my understanding and interpretation).

05-23-2002, 03:26 PM
Exactly, thatīs what it does... compensating that effect, because it canīt be thoroughly fixed.
I checked out several guitars with the Buzz Feiten system. Itīs a different feel to play those, takes some time to get used to it. Whoever is interested should definitely check it out.
My opinion, though:
After like 50 years of electric guitar and centuries of acoustic guitars, I would say that most of us have grown used to that slight "out of tune" effect... weīre used to that sound and we donīt notice it as "wrong" anymore.
Thatīs one reason why I am not using a BF-equipped guitar usually. That means, I used one or two when doing sessions, but I donīt own one. My regular electric guitars are set up as good as possible, and Iīd say that on those, the "out of tune"-thing is not really noticeable. So I didnīt get a BF-system yet.
On acoustic guitars, intonation is a way more critical subject. And itīs usually harder to fix that on acoustic guitars ( since you canīt adjust the intonation of the single strings as easily as on a regular electric guitar )
So most of the time, itīs a matter of getting used to it or compensating it in other ways...

I could go a bit more into the detail, but I guess Iīm being too long-winded already, so...

Warm regards

05-24-2002, 03:44 PM
Hi Bongo Boy!

Yea - now I got what you mean by moving your bridge. Well that might work out of you do it with a pharmaceutical precision. But you risk to obtain the wrong pitches picked at the other parts of your fretboard as the ralative fret division pattern of the string length would be moved as well.

And thank you Eric for info about Buzz Feiten System!

Ultra mega best regards,


When the music's over turn off the lights!

05-24-2002, 04:45 PM
Uhmmm... my recommendation would be to have all intonation-work involving moving the bridge on an acoustic guitar should be done by an experienced luthier.
It might be expensive to let a luthier do it, but itīs easy to ruin a guitar if you go "trial and error" on your own...
And even if you move the bridge, it might only work for one or two strings... each string has to be adjusted differently, that is the reason why itīs tough to do on an acoustiv guitar.
On one of my nylonstring-guitars, the bridge is bended below the G-String... it was done by the luthier. That way, the G-string is just a tiny bit shorter and therefore its intonation is kinda right...
Just my opinion, though
Warm regards

NP: Bruce Springsteen- The Ghost Of Tom Joad

Bongo Boy
06-15-2002, 05:24 PM
The bridge I'm thinking of is adjustable for each string, independent of the others (about 4-5 mm, I'd say). Still, I think everything you guys said is valid anyway. For ME to make any adjustments would be equivalent to my adjusting a fine mechanical chronometer (even if I thought I had a reason to)!

06-15-2002, 08:10 PM
Hi BongoBoy...

Well, I was thinking you were talking about acoustic guitars, because on those, you usually canīt adjust intonation for each string individually.
On electric guitar, you can though. I explained how to do it in my "Setting Up & ..." article a while ago.
It has pictures to show you how to do it on 3 common bridge-models.

Hope this helps

Bongo Boy
07-03-2002, 05:32 AM
Okay I checked out that little piece. I had some problems understanding your comments:

"I check the tuning of the low E-String by hitting the natural harmonic at the 12th fret. If it is in tune (I am checking all that with a tuner, by the way), I compare that harmonic with the actual note at the 12th fret (the fretted note, that is). The pitches of those should be the same. "

The "natural harmonic at the 12th" vs the "actual note at the 12th" is the part that doesn't make sense. How do you 'hit the natural harmonic at the 12th fret'? I'm totally lost.

But all this aside--your goal is to have the frequency at the 12th exactly double that of the open string, right?

07-03-2002, 11:06 AM

what I mean is:
First you play the natural harmonic at the 12th fret. Do it like this: put your finger on the string above the 12th fret, just lay it on there without pressing down the string. Then pick the string and immediately remove the finger from that 12th fret.
What you should hear is an harmonic, pitched an octave above the open string ( and yes, you also could use the open string instead ).
Then press down the string the normal way, as if you want to fret the regular ( non-harmonic ) note at the 12th fret. That fretted note and the harmonic should have the same pitch...

Hope this helps
Warm regards

07-03-2002, 11:12 AM
Touch lightly (do not fret) the string at (directly above) the twelfth fret, pick the string and release the left hand finger. This should produce a node in the string vibration at the 12th fret. you sould hear the result as the sum and difference between the two halves of the string as they vibrate creating the 'natural harmonic' one octave above the open string.

Bongo Boy
07-03-2002, 10:30 PM
...this definitely falls into the "amazing stuff I learned on the web' category. Thanks as always.