B string intonation problems

[mattwood]

I hate the B string on one of my guitars. I can tune it perfectly to B in the open position and move to the third fret and it's +4 sharper. It stays sharp as I move up the neck and gets sharper when I am fingering a more difficult chord. I'm assuming this is a nut issue but not sure how to go about fixing this as I've never done any work on the nut. Any help would be appreciated.

[Zaam]

I would just take it to a good tech. Most likely they will modify the saddle to move the string breakpoint back a bit (away from the soundhole). Fairly routine adjustment, but probably not something you should tackle by yourself.

[mattwood]

Originally Posted by Zaam

I would just take it to a good tech. Most likely they will modify the saddle to move the string breakpoint back a bit (away from the soundhole). Fairly routine adjustment, but probably not something you should tackle by yourself.

That's a good idea but finding one around where I live is the challenge. As I have looked more at this issue it seems all of the strings get sharp as I go up the neck but the B string tends to stand out the most to my ear.

[abn556]

Leaving aside setup issues like intonation and saddle adjustments for a tech question, there are “sweetened” tunings on a Petersen tuner that take into account B string issues. I am not sure about these functions on other tuners as I use a Petersen Strobe tuner. It has all kinds of different tunings programmed into it.

[ljguitar]

Originally Posted by mattwood

I hate the B string on one of my guitars. I can tune it perfectly to B in the open position and move to the third fret and it's +4 sharper. It stays sharp as I move up the neck and gets sharper when I am fingering a more difficult chord. I'm assuming this is a nut issue but not sure how to go about fixing this as I've never done any work on the nut. Any help would be appreciated.

Hi mattwood…
Saddle issue not nut…

You need to have the saddle compensated by someone who does know how to do it well. And in conjunction, you should have the action set properly. Like magic…

Often by the time people notice intonation issues to the point they are determined to fix them, they have already altered their action by first sanding/shortening the saddle, which should be the last adjustment done when setting action.

First step is checking nut slot depth, next setting the truss rod for proper relief and lastly, (if needed) altering the saddle for height. Then intonating the saddle is most effective.

In case you've not discovered it, the 2nd string is not the only string which doesn't play nicely in tune when fretted.

[TheGITM]

Originally Posted by ljguitar

Hi mattwood…

First step is checking nut slot depth, next setting the truss rod for proper relief and lastly, (if needed) altering the saddle for height. Then intonating the saddle is most effective.

There are some different schools of thought on setup steps... here's mine:

1a. Check neck relief AND geometry to bridge/saddle
---Capo on 1st fret, push down on 14th fret, measure string gap at 8th fret
---Should be in the range of .005" to .012" (1mm-3mm), depending on preference
1b. Straight edge check from fingerboard to bridge
---If straight edge is noticeably below the top of the bridge there is a geometry problem that may require a neck reset

2. Assuming step 1a and 1b are good - check nut
---Measure string gap on 1st fret for each string by holding down each string at the 3rd fret and tapping on the top of the 1st fret
---String should just clear the fret so a little 'tap' should be a barely noticeable 'click'
---Adjust nut, as necessary
---NOTE: if frets are noticeably worn down significantly, you may want to stop here and address the frets

3. Once relief is set and the nut is set, now you can look at the string gap at the 12th fret to determine what saddle adjustments might be needed
---If the action is high at the 12th fret and you want to lower it, you will need to take 2x that amount off at the saddle
---So, if you want to drop the action at the 12th fret by 1mm, you would need to shave 2mm off of the saddle
---If the action is low at the 12th fret and you want to raise it, you would need to add 2x that amount to get to your desired action
---You can either shim the saddle, or replace it -note: if you shim the saddle, I recommend using a shim made from the same wood as the bridge, if possible

That's my basic checklist of steps. I should add, though, the very first thing you should do if you're looking at a guitar for the first time, is sight down the neck from above looking at the nut, frets, and saddle to make sure everything looks parallel. Before doing anything, you want to be sure there is not a twist in the neck. If there is, you really don't want to do anything else... except cuss and pray it's under warranty.

Edit to add: The other potential issue is more related to any residual fret buzz that might be present after setting the action - you may need to check for/correct any unlevel frets.

Edit to the edit: I would take care of all of the potential setup issues first, then address any remaining intonation issues.

[mattwood]

Originally Posted by TheGITM

There are some different schools of thought on setup steps... here's mine:

1a. Check neck relief AND geometry to bridge/saddle
---Capo on 1st fret, push down on 14th fret, measure string gap at 8th fret
---Should be in the range of .005" to .012" (1mm-3mm), depending on preference
1b. Straight edge check from fingerboard to bridge
---If straight edge is noticeably below the top of the bridge there is a geometry problem that may require a neck reset

2. Assuming step 1a and 1b are good - check nut
---Measure string gap on 1st fret for each string by holding down each string at the 3rd fret and tapping on the top of the 1st fret
---String should just clear the fret so a little 'tap' should be a barely noticeable 'click'
---Adjust nut, as necessary
---NOTE: if frets are noticeably worn down significantly, you may want to stop here and address the frets

3. Once relief is set and the nut is set, now you can look at the string gap at the 12th fret to determine what saddle adjustments might be needed
---If the action is high at the 12th fret and you want to lower it, you will need to take 2x that amount off at the saddle
---So, if you want to drop the action at the 12th fret by 1mm, you would need to shave 2mm off of the saddle
---If the action is low at the 12th fret and you want to raise it, you would need to add 2x that amount to get to your desired action
---You can either shim the saddle, or replace it -note: if you shim the saddle, I recommend using a shim made from the same wood as the bridge, if possible

That's my basic checklist of steps. I should add, though, the very first thing you should do if you're looking at a guitar for the first time, is sight down the neck from above looking at the nut, frets, and saddle to make sure everything looks parallel. Before doing anything, you want to be sure there is not a twist in the neck. If there is, you really don't want to do anything else... except cuss and pray it's under warranty.

Edit to add: The other potential issue is more related to any residual fret buzz that might be present after setting the action - you may need to check for/correct any unlevel frets.

Edit to the edit: I would take care of all of the potential setup issues first, then address any remaining intonation issues.

I happened to find someone in my area who works on guitars and took my guitar to him and he said much of what you recommended. He feels there is too much relief in the neck but also found the nut slots were too low and recommended filling them and reslotting them. He also said that there were a few frets that had raised that need to be lowered. Basically the strings were too low on the first fret but too high up the neck. The only other thing he found was that the bridge and saddle were slanting towards the sound hole. There is some belly behind the bridge which I guess is the culprit. We talked about the possibility of using a bridge doctor but since it's a narrow bridge a hole can't be drilled and I don't really want to do that He thought that issue could be addressed later if needed. He didn't find the intonation issues to be as bad as I thought they were and part of the culprit may have been me pressing down too hard due to the action. Once he gets the other things done he is going to lower the action just a little at the saddle. Thanks for all of the replies.

[rick-slo]

Originally Posted by mattwood

I hate the B string on one of my guitars. I can tune it perfectly to B in the open position and move to the third fret and it's +4 sharper. It stays sharp as I move up the neck and gets sharper when I am fingering a more difficult chord. I'm assuming this is a nut issue but not sure how to go about fixing this as I've never done any work on the nut. Any help would be appreciated.

You could capo the guitar say at the first or second fret. Get it tune when capoed there and see if still the B string sounds shaper than the other strings as you fret up a little higher and if so the nut is not the issue.

Usually the B string at the saddle is recessed a little a further from the nut. If your saddle does not do that it could be an issue. A lighter gauge string will reduce the sharpness a bit.

[Glennwillow]

I notice this problem on one of my guitars. I will often simply tune my guitar to the D note (that is, playing the B string on the third fret). For some reason a slightly flatted B string played open doesn't sound to my ear like an obviously out-of-tune string.

On another one of my guitars, the low E-string shows up as sharp when playing a G note (6th string, 3rd fret), and so I often tune that E string played at the 3rd fret. Again, the slightly flat open E string doesn't seem to show up as out-of-tune when I do this.

It's a fast and simple solution to a problem that might be a hassle to solve otherwise.

- Glenn

[Merlemantel]

Is the action generally high? I would start there - high action can cause notes to sharp up the neck. Then go from there.

[ljguitar]

Originally Posted by mattwood

…I happened to find someone in my area who works on guitars and took my guitar to him
…Once he gets the other things done he is going to lower the action just a little at the saddle. Thanks for all of the replies.

Hi mattwood
Good for you…

I hope the transformations are amazing, and pleasing to you!

[nikpearson]

Originally Posted by TheGITM

There are some different schools of thought on setup steps... here's mine:

1a. Check neck relief AND geometry to bridge/saddle
---Capo on 1st fret, push down on 14th fret, measure string gap at 8th fret
---Should be in the range of .005" to .012" (1mm-3mm), depending on preference
1b. Straight edge check from fingerboard to bridge
---If straight edge is noticeably below the top of the bridge there is a geometry problem that may require a neck reset

2. Assuming step 1a and 1b are good - check nut
---Measure string gap on 1st fret for each string by holding down each string at the 3rd fret and tapping on the top of the 1st fret
---String should just clear the fret so a little 'tap' should be a barely noticeable 'click'
---Adjust nut, as necessary
---NOTE: if frets are noticeably worn down significantly, you may want to stop here and address the frets

3. Once relief is set and the nut is set, now you can look at the string gap at the 12th fret to determine what saddle adjustments might be needed
---If the action is high at the 12th fret and you want to lower it, you will need to take 2x that amount off at the saddle
---So, if you want to drop the action at the 12th fret by 1mm, you would need to shave 2mm off of the saddle
---If the action is low at the 12th fret and you want to raise it, you would need to add 2x that amount to get to your desired action
---You can either shim the saddle, or replace it -note: if you shim the saddle, I recommend using a shim made from the same wood as the bridge, if possible

That's my basic checklist of steps. I should add, though, the very first thing you should do if you're looking at a guitar for the first time, is sight down the neck from above looking at the nut, frets, and saddle to make sure everything looks parallel. Before doing anything, you want to be sure there is not a twist in the neck. If there is, you really don't want to do anything else... except cuss and pray it's under warranty.

Edit to add: The other potential issue is more related to any residual fret buzz that might be present after setting the action - you may need to check for/correct any unlevel frets.

Edit to the edit: I would take care of all of the potential setup issues first, then address any remaining intonation issues.

0.005” to 0.0012” is not 1 to 3 mm. Closer to 0.1 to 0.3 mm. Those pesky decimal points! In my experience 0.010” is as much relief as anyone needs and a little less can often make for a nicer playing instrument.

A high action will nearly always cause notes to fret sharp as you move up the fingerboard which is why you need to set relief, nut slot height, and then saddle height in that order. Once that’s done any intonation issues can be tweaked by moving the string contact point on the saddle, providing there’s sufficient width. The angled saddle slot used with nearly all steel-string instruments offers ball-park compensation, but to get things just right needs fine adjustment.

[Sasquatchian]

All of my acoustic guitars are the same in this regard to a small degree, even after being set up professionally and had custom intonated saddles. It's just one of those little imperfections we have to live with. John Prine used to say that he tuned his B string a tick flat "for that mountain sound" but I think he was really doing it so his C and D chords sounded better. I do the same as what was mentioned above and tune the B string a couple of cents flat and check to make sure the D note is correct and after that the blend on the chords is sounding pretty darned great.

I also made my one saddles where there is a small step in the saddle, where it's a snug fit into the saddle slot but the actual saddle material is slightly wider above the slot, giving a very slightly greater range of intonation adjustment possibility, even if it's just one or two cents. Was it a pain to do? Yep. Took a couple of hours but now it's done and it really seemed to work well.

And the older I get and the better my ears seem have gotten in terms of pitch, as ol' Robert Keen likes to say, "it's the little things..." that matter.

I also bought one of those Stew-Mac nut gauge dial indicator tools where you can measure the string height over the first fret or any fret for that matter, and determine if your nut slots are deep enough or not. A nut slot that is not deep enough will require more string stretch to fret in the first few frets causing the note to tend to want to go sharp, but if you get that wrong and go too deep in the slot the string will buzz. It's quite nice to be able to actually measure the string height in how many thousandths over the fret it is and it give you an actual number and not just guessing or by feel and then it's also something that reproducible later on.

[TheGITM]

Originally Posted by nikpearson

0.005” to 0.0012” is not 1 to 3 mm. Closer to 0.1 to 0.3 mm. Those pesky decimal points! In my experience 0.010” is as much relief as anyone needs and a little less can often make for a nicer playing instrument.

Yeah, well... I'm an idiot. Thanks for the correction.