Another Intonation ?

[mljohn]

I was checking my intonation the other day and I found that my open notes and twelvth fret harmonics are right on, but my fretted notes from the twelvth fret on up are just slightly flat on each string.(Using a Korg digital tuner)

I can play two note chords(I,V) on any combo of strings above the twelvth fret and they sound clean, but the single notes are a little flat. They seem to be equally flat on each string.

I believe I read somewhere that moving your saddles toward the nut corrects tuning that is flat, and toward the bridge corrects for sharpness.

Anybody out there with a similar problem or an idea on how to correct it?

[Bruce Lindfield]

But moving the saddles back or forward will then make your 12th fret notes out of tune. If you're already intonated at the 12th fret, then moving the saddles won't help.

The notes above the 12th fret are always going to be very slightly out of tune - any fretted instrument is a compromise on intonation. Also, the higher the action, the more you will be "pulling down" on the strings and therefore affecting intonation.

As a general rule - though experience; I don't know the reasons for this - on cheaper basses I have tried this is more of a problem and less on "high end" expensive basses. I tend to try a lot of basses and this is something I always look out for - some people aren't bothered, though as they don't play much above the 12th fret.

[bassdude]

all digital devices including tuners are only accurate to one digit. After you intonenate your bass at the 12th fret you can reintonate it at the 24th fret It will only check true if bring the tuning up slowly to pitch from below the pitch untill it is just in tune. then check the 24th fret. you may have to do this several times to make it work. If you go back and forth between the 24th and the 12th fret you can get it properly intonated.

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Carl

[john turner]

quote:

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Originally posted by mljohn:
I was checking my intonation the other day and I found that my open notes and twelvth fret harmonics are right on, but my fretted notes from the twelvth fret on up are just slightly flat on each string.(Using a Korg digital tuner)


the harmonics will be on if the open note is on. what you need to do is get the open note on, then the 12th fret _fretted_ on also.



I believe I read somewhere that moving your saddles toward the nut corrects tuning that is flat, and toward the bridge corrects for sharpness.

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that is correct - if your harmonic is on and the fretted note is flat, move the saddle towards the nut, and towards the bridge for sharpness.


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you wanna see a frustrated guitarist? let a guitarist try to do something useful on one of my basses. _THAT'S_ a frustrated guitarist.

[Bruce Lindfield]

I assumed that what mljohn was saying is that he has checked the 12th note fretted against the 12th note harmonic and they match - this is the standard procedure - so moving the saddles won't help.

In the past I have had lots of basses (usually cheaper ones)where this has been a problem and I have heard other people mentioning this on this and other bass-related sites. I can rememeber people actually saying they don't care as they don't play above the 12th fret anyway.

[john turner]

quote:

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Originally posted by mljohn:
I was checking my intonation the other day and I found that my open notes and twelvth fret harmonics are right on, but my fretted notes from the twelvth fret on up are just slightly flat on each string.(Using a Korg digital tuner)

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i was assuming that since he was saying that the fretted notes from the 12 fret on up are flat, then his intonation is off. it sounds like he doesn't know how to check his intonation.

if your 12th fret fretted note is flat, and your harmonic is right on, then you need to move the bridge saddle forward, towards the nut.

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you wanna see a frustrated guitarist? let a guitarist try to do something useful on one of my basses. _THAT'S_ a frustrated guitarist.

[mljohn]

quote:

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Originally posted by john turner:
i was assuming that since he was saying that the fretted notes from the 12 fret on up are flat, then his intonation is off. it sounds like he doesn't know how to check his intonation.

if your 12th fret fretted note is flat, and your harmonic is right on, then you need to move the bridge saddle forward, towards the nut.

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That's what I'm saying, the 12th fret harmonics are on, but the fretted notes from the 12th-24th frets on each string are flat. Just barely, but enough that I can tell the difference.

[Rumblin' Man]

The cure is easy, take it to a repairman for intonation, and a setup probably wouldn't hurt either.

[john turner]

setting one's intonation is very easy.

step 1. tune the string against an accurate tuner

step 2. notice that the harmonic at the 12th fret will be in tune when the string is in tune - this is a function of string physics, and will always be the case - if string is in tune, harmonic at 12 fret will be too, regardless of intonation.

step 3. fret the string at the 12th fret. if the string is flat, move the bridge saddle a little bit towards the nut. if string is sharp move away from the nut.

as you move the bridge saddles, the string will go out of tune, in fact you probably will have to detune to be able to move the saddles, so after you make an adjustment, go back to step 1 and repeat.

the 12th fret harmonic and fretted note should be the same. if you want to get really picky, you can repeat at the 24th fret - you will find that you will end up needing to compromise between intonation at the 12 fret and at the 24th, even with an excellent bass, it will be impossible to get them perfect.

one aid to good intonation is using taper-core strings - by providing a more precise break point at the bridge, it facilitates better intonation.

good luck

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you wanna see a frustrated guitarist? let a guitarist try to do something useful on one of my basses. _THAT'S_ a frustrated guitarist.

[eli]

If you're still having trouble, try three things:

1) get new strings. Old strings can for a variety of reasons become inpossible to intonate.

2) Lower your action.

3) if you don't have 24 frets, use the harmonic at the 19th. Your bass's fret positions may not be perfect and you may have to settle for a slightly out of tune 12th and a slightly out of tune 19th (one is sharp and the other flat), but you bring them to the closest possible compromise. If your frets are not perfect there is very little else you can do -- except, of course, rip 'em out and intonate with your fingers on the fly.

[Reg]

it is possible that the action on your bass was designed to be sligthly higher. But that it something that would be worth fixing if it feels right at the moment.

If could always add a small bent to your notes abouve the 12th. thus making them slightly sharper, and in tune.

[pkr2]

Something just dawned on me. Since a digital tuner displays mathematically derived results and the scales(that we use) are tempered scales, does it seem reasonable that a digital tuner will indicate a small error even though it's ( the string) tuned as well as it can be tuned. I don't really know but it's food for thought. I have heard lots of guitar players say that the B string on a guitar always has to be tweaked even though a tuner shows it to be in perfect tune.

[eli]

You're right, it's impossible to place frets to be in tune for any chord. There was a company 20 years ago who was selling classical guitars with interchangeable fingerboards, each tempered to a different set of keys -- one for C through A, one for E through C#, etc. The frets were not continuous, but segmented -- each segment tuning its individual pitch pretty well for that group of keys.

But the tuner is only looking for the octave which is always an exact multiple. That's not the problem. The proper placement of frets frets should be in tune with the tuner, tempered for all keys.