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Edspyhill05
08-03-2017, 11:09 AM
Someone gave me an old Kingston baritone ukulele from the mid '60's that was somewhat mistreated. It's all laminate mahogany.

The original finish was covered with varnish, even the fingerboard. The bridge and saddle, both rosewood, were warped. I stripped the Uke and put on a new bridge.

All is well except when I tune the open strings all the frets are sharp. If I tune the notes at the first fret, open strings are flat but the frets are relatively in tune. The second saddle gives a temporary high action which has an effect on notes as I fret up,the neck.

My question is what would cause the the fretted notes to be sharp when the Uke is tuned at the nut? I aligned the new bridge so the saddle was where the old saddle was located. Do you think the original bridge/saddle was positioned incorrectly?

Ed

Titchtheclown
08-03-2017, 12:43 PM
It sounds to me like the nut is the problem. Either too high or too far away from the first fret.

Edspyhill05
08-03-2017, 06:30 PM
It sounds to me like the nut is the problem. Either too high or too far away from the first fret.

The nut is wood. I'll experiment first with filing the face of the nut back and see if that fixes the problem. If that fixes the problem then I'll make a new nut. I tried moving the witness point of the saddle forward and back but that had no effect. This baritone ukulele has been fun to work on and learn. i'll post the results.

Thanks,

Ed

anthonyg
08-03-2017, 07:38 PM
I agree that it sounds like the nut is too far away from the centre of the 12th fret. This is a fairly common problem. One solution is to carefully file away the end of the fretboard to move the saddle closer.

Here's a quick experiment/solution. Place a matchstick on the fretboard up against the inside of the nut under the strings. Has it fixed the intonation problem?

Michael Smith
08-03-2017, 07:53 PM
[QUOTE=Edspyhill05;1985528]The nut is wood. I'll experiment first with filing the face of the nut back and see if that fixes the problem. If that fixes the problem then I'll make a new nut. I tried moving the witness point of the saddle forward and back but that had no effect. This baritone ukulele has been fun to work on and learn. i'll post the results.

If you file the nut back you will be going in the wrong direction. Your symptons indicate a nut too far from the first fret. or maybe you aren't rolling the strings off edge of the nut. Being wood it might have become worn? Or your action is way too high?

sequoia
08-03-2017, 08:06 PM
Yes, it sounds like the uke has intonation issues. Common in ukuleles. If the scale length is not properly compensated, notes will sound sharp as you fret the notes up the neck. The reality is that all ukes with a straight saddle will suffer intonation issues. The question becomes: Just how bad is it? If you can live with it, just play the uke and enjoy. This is a complex issue and there are many past posts on the issue. Do a search.

Michael N.
08-03-2017, 11:27 PM
Of course it could be a combination of poor nut placement, poor saddle placement, high action and badly placed frets.
There's only one way to address this issue, start eliminating the possibilities one by one. You need to start measuring things with an accurate rule.

ProfChris
08-04-2017, 05:30 AM
Measure for sure!

Go to this web page: http://www.liutaiomottola.com/formulae/fret.htm

and find the section "Calculating Fret Spacing for All Frets".

Measure from the *front* of the nut to the 12th fret (in whatever you like, mm is nice and easy, inches needs to be entered in decimal, e.g. 9 1/2 = 9.5). Double that number and enter the result in the Scale length box.

Press "Calculate".

Now you know what the distances ought to be from the front of the nut to the other frets. Measure a sample (say 5, 7 and 9). If they are all too long (on your fretboard) by, say, 1.2mm, then you know you need to shorten your fretboard *at the nut end* by that amount. But check frets 1, 2 and 3 as well before you start cutting or sanding!

If the numbers are all over the place, come back here, tell us the numbers and we'll think about the fix.

If the numbers are correct according to the calculator then measure 12th fret to the peak of the saddle and report that back to us. That should be a little more than the nut-12th fret distance, maybe 2mm.

Do this before cutting, sanding or otherwise altering your uke!

As a guess, your nut is too high and the peak of the saddle is too far forward. I say this because that's usually the main problem with ukes that have never been set up. But it's not unknown for ukes of that age to have different problems, so it's only a guess.

Edspyhill05
08-21-2017, 08:51 AM
Update: today I finally had time to work on this baritone Uke. I took just a bit of wood off the front of the nut and now the fretted notes are in tune with the open strings. I can't explain this but it may have been the nut was uneven and the nut slots were cut incorrectly. I'm guessing that the forward string nut slots were filed. So the actual witness point was back toward the tuners.

This old baritone ukulele sounds awesome for its age and being all laminate wood. The last task is to lower the saddle slowly. It's the second one I made for the new bridge and wanted to wait until I fixed the nut problem.

I will go though all your posts and learn much more about scale length, intonation, string height, saddle adjustment.

I may switch to baritone ukulele.

Thank you to all and apologies for the delayed update.

Ed

Choirguy
08-21-2017, 04:09 PM
Yes, it sounds like the uke has intonation issues. Common in ukuleles. If the scale length is not properly compensated, notes will sound sharp as you fret the notes up the neck. The reality is that all ukes with a straight saddle will suffer intonation issues. The question becomes: Just how bad is it? If you can live with it, just play the uke and enjoy. This is a complex issue and there are many past posts on the issue. Do a search.

Side question here: Do you have any research on this conclusion? Obviously no fretted instrument can be perfectly in tune--regardless of saddle configuration. And if straight saddles are the issue, why would they be used on a majority of instruments? I can see crooked frets and bridges being an issue--but I would like to get further informed.

Beau Hannam Ukuleles
08-21-2017, 06:06 PM
Thousands of 1970's Martin guitars have bridges in the wrong place- the cause isn't known but i've heard the story that a employee was fired and changed the saddle location jig by 1/8 or so.

sequoia
08-21-2017, 06:08 PM
Side question here: Do you have any research on this conclusion? Obviously no fretted instrument can be perfectly in tune--regardless of saddle configuration. And if straight saddles are the issue, why would they be used on a majority of instruments?.

There is lots of research done on this question that goes back to Bach (The Well Tempered Clavier) and even further to Greeks of three thousand years ago. It is just basic physics... Why are straight saddles used on the majority of ukuleles? Two reasons I think: It is simpler and cheaper and perhaps it is good enough. Part of the charm of the ukulele I think is that it is basically an instrument that is meant to be played on the beach under the moonlight and not in a parlor with perfect intonation like a Stradivarius violin. (That being said: Intonation issues drive me a little crazy with the uke too.)

Here is the thing: In order to get close to perfect intonation on an ukulele, due to the differing thickness of the strings in standard ukulele tuning, each string would need a seperate distance at the saddle (or nut) and this is not easy to do. So the saddle would need to be cut in to 4 pieces and set in the bridge at a seperate distances from the nut with proper compensation for sting stretching at a given string height (action). A lot to calculate and build. Absolutely those numbers can be calculated to a find degree of error. But ultimately is it worth the time and effort? Thus the straight saddle. It is good enough.

Choirguy
08-21-2017, 07:34 PM
Well, Lanikai tried to make an adjustable nut work, and in the process abandoned the entire line (and haven't been making much of a splash in 2017 after NAMM). I'm not attacking you Sequoia--actually trying to make the call of..

"Does anyone know of printed research that addresses this issue?" That's to UU as a whole.

I had a discussion with someone about radius fretboard and compensated saddles, partly due to the (now $95) $29 Enya EUR-X1 ukulele. Was that saddle created for that ukulele? Was Martin's? Is there really a difference between the C and E strings and their lengths as a result of that saddle? What if a Martin soprano had a straight bridge?

It's just something I 'm curious about and would be interested in some deeper conclusions on the topic versus just acknowledging "general knowledge" that it goes back to Bach and the Greeks.

anthonyg
08-21-2017, 11:22 PM
Well, Lanikai tried to make an adjustable nut work, and in the process abandoned the entire line (and haven't been making much of a splash in 2017 after NAMM).

Meh. Lanikai made a HALF arsed attempt at better intonation using an adjustable SADDLE, and a compensated nut. They claimed a lot but didn't execute it properly. I almost suspect they didn't execute it properly deliberately. They KIND of had the right idea in compensating the nut but they over did it. Its like no one actually made up a prototype first to test the idea.

The saddle was better but in practice I suspect it was just used in order to avoid placing the saddle accurately in the first place. Since it was adjustable it was kind of placed all over the place. The Tuna ukes I played myself also suffered from warped necks across the line.

Just a poor effort all around.

ProfChris
08-22-2017, 12:11 AM
Here is the thing: In order to get close to perfect intonation on an ukulele, due to the differing thickness of the strings in standard ukulele tuning, each string would need a seperate distance at the saddle (or nut) and this is not easy to do. So the saddle would need to be cut in to 4 pieces and set in the bridge at a seperate distances from the nut with proper compensation for sting stretching at a given string height (action). A lot to calculate and build. Absolutely those numbers can be calculated to a find degree of error. But ultimately is it worth the time and effort? Thus the straight saddle. It is good enough.

Each string does need to be a different length, depending on its thickness, but achieving that doesn't require a four-piece saddle.

On ukes the difference in length required is less than 3mm (1/8 inch). So all a builder need do is use a saddle which is at least 3mm wide, place the bridge so the front of the saddle is at the right place for the thinnest string, and then file back for each of the other strings until the fretted note at the 12th fret is an octave above the open note. For someone in practice this is probably 10-15 minutes work. If the frets are placed correctly, all the other notes will be very close (but not quite exact, equal temperament is a compromise).

On a budget uke, this extra amount of time eats substantially into the profit margin, thus the straight saddle.

Also, the amount of compensation changes with two variables: the action at the 12th fret (the higher the action, the more compensation is required), and the type of string (thin, dense fluorocarbons require less compensation than fat, less dense Aquila Nylgut). That might be a reason for a higher end uke still to have a straight saddle, expecting that the buyer will have the final setup customised for preferred action and string choice.

finkdaddy
08-22-2017, 01:09 AM
Each string does need to be a different length, depending on its thickness, but achieving that doesn't require a four-piece saddle.

On ukes the difference in length required is less than 3mm (1/8 inch). So all a builder need do is use a saddle which is at least 3mm wide, place the bridge so the front of the saddle is at the right place for the thinnest string, and then file back for each of the other strings until the fretted note at the 12th fret is an octave above the open note. For someone in practice this is probably 10-15 minutes work. If the frets are placed correctly, all the other notes will be very close (but not quite exact, equal temperament is a compromise).

On a budget uke, this extra amount of time eats substantially into the profit margin, thus the straight saddle.

Also, the amount of compensation changes with two variables: the action at the 12th fret (the higher the action, the more compensation is required), and the type of string (thin, dense fluorocarbons require less compensation than fat, less dense Aquila Nylgut). That might be a reason for a higher end uke still to have a straight saddle, expecting that the buyer will have the final setup customised for preferred action and string choice.

This is fantastic information! Thank you for sharing this! My question: In your opinion, would the buyer of a high-end uke prefer to have the saddle compensated for the strings and action of the instrument at time of sale, or would the preference be to have higher action and a straight saddle so that they can have it set up with the strings and action that they personally prefer?

ProfChris
08-22-2017, 03:53 AM
Depends, I'd say. Someone who plays mainly below the 5th fret might prefer the saddle already compensated, as lowering the action wouldn't affect the intonation there very much. Someone who spends time on the higher frets, especially on the C string, might want the full range of options which an uncompensated saddle allows for adjustment.

Choirguy
08-22-2017, 04:15 AM
So all a builder need do is use a saddle which is at least 3mm wide, place the bridge so the front of the saddle is at the right place for the thinnest string, and then file back for each of the other strings until the fretted note at the 12th fret is an octave above the open note.

Can you name a builder who does this? I'd be interested to look them up and see what that actually looks like. Then to play one and compare it to my other ukes that do play in tune at the nut and 12th fret while having a straight saddle.

Sven
08-22-2017, 06:00 AM
I do that on all my ukes. As Chris says, a few minutes work is all it takes. I've played loads of ukes with straight saddles and it seldom bothers me, but mine are better in case one checks intonation with a tuner. And it looks classy.

A few pics:

102506

102507

https://lh3.googleusercontent.com/-6aZYC3jrx9Y/VpipPwBv9ZI/AAAAAAAADsA/qlHaO1pYveY/s640/blogger-image-1477745456.jpg

https://lh5.googleusercontent.com/-taTBcc4wZD8/U6_RRnFrCCI/AAAAAAAACrg/OzIUCxlCQBo/s640/blogger-image-1224362031.jpg

sequoia
08-22-2017, 08:12 PM
Thanks Sven. That does look classy...

This thread has been covered before almost ad-nauseum. But it is soooo important to how the instrument ultimately sounds so it can hardly be over emphasized in my opinion. It is a very complex issue (at least to me) because there are a lot of potential variables in the equation. I would like to say again that the straight saddle perpendicular to the nut is always going to have some intonation issues. A best, only one string will be spot on.

I admit the 4 piece saddle(?!?) is probably ridiculous in practice and the compensated saddle with a file is the way to go. It depends on what kind of strings the player is going to use and what the height of the action is that they like. This is truly custom work and should be why a customer pays big bucks for a high end instrument. This also implies that the luthier and the customer meet and work out the variables face to face and really dial it in.

The reality is that most ukulele players that are not professional performers or advanced amatuers don't really know what kind of strings they want or the height of the action they prefer. This is where a true high end luthier should work with the customer one on one and intonate the uke so that it allows the customer to get the best sound possible according to his or her preferences and ability. How often does that happen? Not much I think. Therefore the luthier makes the best guess on what the player will like. In the mass market, I think the manufacturer just uses the straight saddle because it is going to be good enough for most players.

By the way Sven, from the picture it seems to show a pretty radical angle offset on the saddle slot. Is this part of the compensation calculation or is this an "anti rotation" calculation or both? Oh and also, if you are so inclined (please), could you post the measurements on each string distance. That would be really interesting. If you don't want to, that is ok too.

Sven
08-23-2017, 12:02 AM
Ha ha, I am as inclined as my saddles! I angle the saddle to prevent rotation, letting the strings push it down into the bridge. I agree that the ones I show in the previous post might be a tad too angled - one could argue that the string length would shorten if the saddle was lowered. Then again, a lower saddle would mean less stretch when fretting so another one could argue that this means less need for compensation.

When I chose the angle I was aiming to bisect the angle formed by the string, thinking it looked good. And it works for me. Maybe I'm underthinking this, but the ukulele is after all such a happy little instrument... it goes drring drring plunk plunk and the beer is cold and everyone so friendly.

ProfChris
08-23-2017, 12:17 AM
I don't think anyone does this by measuring. The process is pretty simple for me:

Compare 12th string harmonic with fretted note at the 12th.

If the fretted note is sharp, take the saddle back a little at that point (I just slacken the string and move it out of the way).

Repeat until both notes are the same.

I usually do this with a chisel, and then when all four strings are intonated I remove the saddle and tidy up my chisel marks with sanding.

For a 13 inch scale soprano using Aquila strings with action 2.5mm at the 12th the C string compensation will be around 2.5mm, the E string about 1.25mm, and the G string maybe 0.5mm. The numbers will be lower on longer scales.

This is something a player can learn to do for him or her self. Buy a spare saddle, sand it to fit the slot, and then go to work. However, the first thing to fix is the nut height, which might require deepening the saddle slots. A high nut is the worst culprit for poor intonation.

Once the nut is sorted, drop in the spare saddle and get the height right at the 12th fret. I find 2.5mm (measured from top of fret to bottom of string) good for most players, but a heavy strummer might want 3mm, while a player of fast runs might want 2mm. Take the saddle down by sanding the bottom, marking a line on it to make sure you sand evenly. If you go too far, throw the saddle away and buy another one.

When the action height at the 12th is good, set to work on the compensation. A chisel (tiny shavings), baby file, or sandpaper stuck to a thin stick, all will do the job. On a moderately priced factory uke you will have a plastic saddle, which is very easy to work. Bone or some hard composite like Tusq is slower work, but not difficult. For first attempts, use something like cardboard to protect the top against slipping with whatever tool you're using.

When you're nearly done, don't forget that the top of the saddle needs to be rounded, so build that in as you're taking the peak back.

And if it all goes horribly wrong, put the original saddle back in and you're no worse off!

sequoia
08-23-2017, 07:56 PM
I don't think anyone does this by measuring.!

Excellent post! Basically dial it in. Good advice.... However, this predisposes that the scale length and compensation is "ball park" close. You are only going to get about a 1/16 inch wiggle room forward or backwards on the saddle, so get it close to begin with.... Also I agree that a the too high nut is responsible for some of these bad intonation issues on poor setups. And also, if you have not done this before, go slow and don't take too much material or you have just ruined your saddle. Hello shim! Saddle shims are totally lame and suck up sound! Use a tuner and go slow. And like he says, have a spare saddle ready to go just in case. Be happy if you can get it to one cent.

Edspyhill05
09-02-2017, 09:09 AM
Update: today I finally had time to work on this baritone Uke. I took just a bit of wood off the front of the nut and now the fretted notes are in tune with the open strings. I can't explain this but it may have been the nut was uneven and the nut slots were cut incorrectly. I'm guessing that the forward string nut slots were filed. So the actual witness point was back toward the tuners.

This old baritone ukulele sounds awesome for its age and being all laminate wood. The last task is to lower the saddle slowly. It's the second one I made for the new bridge and wanted to wait until I fixed the nut problem.

Ed

One last update. The consensus that the nut was too far from the saddle was accurate. Turned out that it is just that the rosewood nut was not slotted properly and it is warped. Someone filed the slots so the high side was toward the tuners. I got the intonation very close but the nut is just not right. The last step will be to make a new bone nut.

I also lowered the saddle to lower the string action. I left it at about 3mm at the 12th fret. I'll leave it there for now.

Thank you to all for your generous and invaluable advice.

Ed

sequoia
09-02-2017, 07:31 PM
Someone filed the slots so the high side was toward the tuners.

Ed

Yes, having the nut in backwards would seriously mess up intonation. Glad everything worked out and ended happily. Aloha.

Edspyhill05
01-08-2018, 06:15 PM
One last update. I got the Uke almost fixed by cutting slots deeper in the old nut, but it was not perfect. So, I finally took the time to order bone saddle/nut material. Saturday I tapped the rosewood nut off the fingerboard. It had an unusual shape that was completely visible only after it was removed. The nut was “crowned” with three surfaces on the top of the nut, and the entire front of the nut was not perpendicular to the fingerboard.

I made a new bone nut, cut the string slots for a low action. This old baritone ukulele sounds so sweet. It is a shame this Uke, since the late 1960’s, was considered a crap instrument that played sour, out of tune chords.

All it took was a new bridge, a new bone saddle, and a new bone nut.

Thanks to all, again, for this discussion.

Ed

Edit: I don’t want to give the impression the Uke now sounds like a solid top instrument. The chords are in tune at least up to the seventh fret. A little fine tuning of the nut will smooth out the intonation a bit more.