how to do intonation ??

[ccoleman]

I just did the intonation of my guitar..

Or I think I did... I am not sure if I did it correctly.

I adjusted string length (saddle position) until the 12th fret fretted frequency was exactly 2X the open string frequency.

Is this the correct way to set the correct intonation ??

[ssjazzrock]

well, no, you need to check the 12th fretted note with the 12th fret harmonic, where you just lightly hold your finger on the string just above the 12th fret wire. Now the harmonic and the fretted note should be pretty darn close. Thats intonation. Its a pain.

[ccoleman]

thanks ssjazzrock, i will check that now. I bet it is darn close if not exactly right, because 12th fret harmonic is normally exactly 2X the open string frequency. be right back.........

[ssjazzrock]

well, its not so much the note ur trying to adjust, its the length of the string, the harmonic will be higher than the fretted note if the string is too short (youll need to move the saddle back toward the bottom of the guitar) and if the string is too long, the harmonic will be lower (youll need to move the saddle closer to the neck) each time you want to move that saddle, you have to detune it a bit, then move the saddle, then tune it up and test it. If you try moving the saddle with it NOT detuned a bit, you risk breaking a string... probably should have mentioned that earlier... sorry.. not quite awake yet...

[RJB]

Actually using the 12th fret harmonic can be off. I had a inexpensive guitar once, from the factory, harmonic was right, but the saddle was off by almost 3/16"! Using the fretted note with a chromatic tuner is more accurate, and combines a little of the players touch into the mix so it's also more accurate during actual playing. (you know those guys with the death grip power chords )

Remember to retune the string after each saddle adjustment. You can also do a quick check by playing the 12th fret note and the same note on the next lower string (12th and 17th, E-B)

[rugburn]

Something I read a long time ago, and it makes sense - do the intonation adjustment with the guitar as you will be playing it - sitting, with it resting on your leg, or standing, with it on the strap - the weight of the guitar, and tension from the way you sit/stand can have a minute difference in the intonation, as the wood stresses differently with the guitar in the different positions. Not sure if this is true, but it's the way I have done it since I read that 15-20 years ago.
Later
rugburn

[mlrpa]

I use a combination of both styles. I get the open note to the 12th fret harmonic correct, then fine tune it with a fretted note, ie: 5th fret A. Then check it against other notes. Yep, a royal pain, but I'm always in tune up and down the neck.

[sumgai]

Guys,

I hate to pee in anyone's Cheerios, but if you use another string on your guitar, which is itself in a questionable state of tune, then you are just compounding your problems.

You must use an external reference standard in order to get where you wanna go. Either a simple guitar tuner, or something radically expensive, it doesn't matter, but you should be able to resolve to the centime. That's what they call a "1/100th" of a semi-tone. (And a semi-tone is equal to going up or down one fret's worth.) I must caution you here that a chromatic tuner does not necessarily mean that it will resolve to the centime, it merely means that it covers all the notes of the scale, not just the six found on a guitar (some tuners are guitar only, or bass only).

For all that I think they are radically and ridiculously overpriced and overhyped, a strobo-tuner will do the necessary job here. Just be sure to bring two checkbooks with you, one won't be enough.

Alternatively, you could use another sound source to compare against, but I don't recommend that. The issue here is too many overtones, which in turn can confuse the ear. Even in a quiet setting like your studio, it can be difficult to use this method. That's why I like a tuner with a visible readout. Even a cheapie will do better than your ear, for this job.

What do I do? I use a $20 Seiko (ST-747), which can do the centime trick. Then I set the length of the string such that when I fret the string at the 12th fret, it reads the same note as the open string. I can easily get "plus or minus" 0 centimes. After that, provided the frets were placed correctly when the guitar was built, the strings will all sound out their notes correctly.

Tip: ssjazzrock says that you must de-tune a string before you adjust a saddle, in order to avoid breaking a string. That's true, but it gets worse.... if you don't de-tune, you run the risk of sawing the groove in the saddle even deeper, a serious infraction of the rules. You can't shortcut this process, not without some risk of damage to your axe.

And finally, rugburn, you're a newbie here, so I really hesitated to say anything, but that tip you read a long time ago about setting the intonation while the guitar is vertical (as you'd use it)..... that's been dis-proved, time and again. Sorry, but this one is in squarely in the pantheon of those "legends and myths that won't die, thanks to the internet".

HTH

And to put paid to the account..... cc, you did do it correctly. I hope you used a tuner, but however you did it, you described the method correctly. If you'd made it a statement instead of a question, I'd've had to +1 you.

sumgai

p.s. Yes, we've covered before the thorny topic of equal temperment, just temperment, and other variations. You can search for them on this forum, or you can google for them, you'll learn a lot by doing so. Wiki pages are a good place to start, IMHO.

[ccoleman]

LOL... yes I used a tuner... actually a tuner software, which is hella accurate, it shows the frequency down to the cent. A great help... thanks for your suggestions.

[RJB]

SG: just to clarify I was only suggesting using the 2 string method as a quick check. Like proving to the "expert" as GC that one string is off. And he does the harmonic test and it sounds ok.

I use an older Boss TU-7 which is good to 1-2 cents. BTW checked the tuner built into the Behringer VAMP. It's as good as the Boss on open strings, but off by a few cents on the E-B 12th fret notes.

[eljib]

I adjust the saddles until fretted and harmonic notes read exactly the same on a tuner. This should be done at the 12th AND the 19th (you'll need a chromatic tuner for the B string at 19). Sometimes it doesn't work exactly for both 12 and 19 if the guitar hasn't been leveled recently, so if that happens I just go for a good balance between the two. Most of our soloing takes place up there anyway, so it makes sense to get it in tune in the second octave. Frets 1-12 have improved intonation as a result.

[mikesr1963]

Well this was made a lot harder that it should be. Relax, it's not rocket science.

[UnklMickey]

mikesr1963 said:

...Relax, it's not rocket science.

you tell 'em mike!


this ain't Rocket science................it's ROCKIN' science!



OMG! did i just coin a new phrase?