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michaeloceanmoon
11-30-2012, 08:32 PM
Hello experienced ukers!
I started playing uke less than a year ago, (though I'm a long time guitarist). I regret not spending $800 on a Collings UT1 which blew me away, yet I didn't know a C chord at the time so my wife wasn't behind the purchase, and I was timid. Now I love uke more than the guitar! After last holidays the only decent uke I could find was the Ohana solid rosewood concert. For $175 it sounds great, but the intonation is off on the E and A strings, (I have to flatten those strings to get chords to sound in tune. Is there anything that can be done? The E and A strings get sharper the further up the neck I go... The G and the C strings are ok though.
thanks!!!

mm stan
11-30-2012, 09:01 PM
I'd take it in and get a set up and some martin M600 strings....good luck..

hmgberg
11-30-2012, 09:32 PM
Like Stan says...get a set up. But first, there are a few things to consider for your own edification. Geometry: the action is higher the further up the neck you go; you are actually stretching the strings when you play, causing them to go sharp. I like my ukuleles set to 3/32" at the 12th fret; if yours is higher than 1/8", it's likely to be contributing to the intonation problem. The saddle: If it is not properly located or shaped, you will have an intonation problem. Measure each string. The distance from the 12th fret to the saddle (where the string breaks across it) should be exactly the same distance as that from the nut to the 12th fret. For example, if the overall scale length is 15", the distance to the 12th fret and the distance from the 12th fret to the saddle should be 7-1/2". If the length is too short to the saddle, your ukulele will be sharp. A luthier can compensate for this by shaping the saddle in such a way as to lengthen the scale. Some ukuleles come with compensated saddles. They are adjusted to compensate for the varying string gauges. However, string gauges vary among different brands. Therefore, strings: While I'd do the measuring first, the next thing I would do is try a different set of strings. I think Ohanas generally come with Aquilla strings. These are considerably heavier than the Martins Stan recommends. The intonation problem may be mitigated with lighter gauge strings.

I'm going to guess that the saddle is a little off, given that the treble side is sharp. A good set up should do the trick.

Newportlocal
11-30-2012, 09:46 PM
Hello experienced ukers!
I started playing uke less than a year ago, (though I'm a long time guitarist). I regret not spending $800 on a Collings UT1 which blew me away, yet I didn't know a C chord at the time so my wife wasn't behind the purchase, and I was timid. Now I love uke more than the guitar! After last holidays the only decent uke I could find was the Ohana solid rosewood concert. For $175 it sounds great, but the intonation is off on the E and A strings, (I have to flatten those strings to get chords to sound in tune. Is there anything that can be done? The E and A strings get sharper the further up the neck I go... The G and the C strings are ok though.
thanks!!!

There is still time. Matter of fact it is almost Christmas.:D

EDW
12-01-2012, 01:00 AM
I would change the strings. I recently had a situation where I was drastically out of tune and putting fresh strings on solved the problem.

Pondoro
12-01-2012, 01:11 AM
Actually the distance from the nut to the twelfth fret is not exactly equal to the distance from the twelfth to the saddle. From the 12th to the saddle should be just a bit more. That difference is the amount of compensation. If all the strings get sharper as you go up the neck it is a sign of inadequate compensation. I have had to move the saddle slightly on a couple of cheap ukes but Ohanas have a good reputation. Measure those two distances very precisely and see if they are equal.

I saw one cheap uke that did about what you are saying - on it three strings were perfect as you played up the neck but one got progressively sharper. I reversed that string and the problem went away. I have no scientific reason for that but I had heard about the trick and I tried it. So if it was my uke I would do the measurement, then report back. I'd reverse the strings because what the hay, it is worth a try. And I agree the action might be too high, check it out. Then try new strings.

Also guitarists have strong fingers, are you mashing down too hard on the strings? That will make them go sharp. It shouldn't affect only A and E but it is a problem sometimes and guitarists need to be warned about it.

patico
12-01-2012, 05:46 AM
should have bought it man.....


i recentrly got my UT1 and it's the best
(also ex long time guitar turned to ukulele)

hmgberg
12-01-2012, 09:58 AM
Actually the distance from the nut to the twelfth fret is not exactly equal to the distance from the twelfth to the saddle. From the 12th to the saddle should be just a bit more. That difference is the amount of compensation. If all the strings get sharper as you go up the neck it is a sign of inadequate compensation. I have had to move the saddle slightly on a couple of cheap ukes but Ohanas have a good reputation. Measure those two distances very precisely and see if they are equal.


Yes, this is correct. The difference is about 5/64" longer to the saddle. We normally position the front of the saddle slot at an equal distance, but then crown the top of the saddle which, in effect, increases the distance adequately and the intonation is generally good.

kenikas
12-01-2012, 12:47 PM
From your post it sounds like your strings are about a year old and you may just need new ones. But as others have said I've had a few ukes that had odd intonation problems and just putting a new set of strings on solved it. Also I think the Ohanas come with Aquilas and I usually prefer Fluorocarbon strings on solid and solid top instruments.

anthonyg
12-01-2012, 01:12 PM
Stating that the G and C strings are OK and its only the E and A strings that go sharp is hinting to me that the nut is possibly not on completely straight. This is something that a luthier can fix without too much trouble.

For your own reference measure it. What's critical is not so much how close to the nominal scale length (nut to saddle) the instrument is rather its, is the total scale length precisely double the nut to 12th fret distance (hopefully a tiny fraction more). I find that if the double the nut to 12th fret distance falls at the leading edge of the saddle with the thickness of the saddle falling further away from the nut than the nominal scale length is then its fine. Measure the nut to 12th fret distance on both sides of the fret board and see if they are precisely identical. Given your issue I wouldn't be surprised to find that its a tiny fraction longer on the A string side than the G string side.

Anthony

michaeloceanmoon
12-01-2012, 08:10 PM
Thanks to all of you for the great advice. After staring at the Uke for a while I noticed ( noticed it a year ago too) that the peg head/ neck has a twist in it. If you look at the nut from the bridge, you can see that the E side dips down towards the back of the uke . So it a sense, the level bridge ends up being progressively higher from the G to the A strings.
Does This Visual Make Sense?
I bought the uke from Pioneer Music in Portland (which was closing it's doors for good the month I purchased... reason why the Collings was $800), so I never made a stink about it. Even with the twisted neck, this inexpensive Ohana CK-50G sounds better than most ukes I've ever played; that includes custom ukes I played at the 2011 ukefest up the gorge. Only the Collings sounded better. I'm sure lots of uke sound better, but my point is that despite the drawbacks, for some reason this is a very good sounding uke.
Anyway, I'm a woodworker/artist who has done some instrument building, so I decided to incorporate everyone's advice by taking matters into my own hands.
I removed the bridge and sanded it down on angle (from the G to the A) to mimmic the angle of the nut. I figured this would shorten the string lengths progressively, and reduce the higher action resulting from a dipping nut and a level bridge.
Whoa!! it actually worked!! I think that I have a bit more sanding to do since the higher frets on E and A still are more sharp, however, my chords and open strings are dramatically more "intoned" than ever before!
I'm super stoked, my uke has never sounded so good. Thanks everyone for being a great sounding board for my question! If there is any more expert advice on refining this I'm open to it.
Ironically, I hurt my wrist later in the day when I finally went back to my workshop, so I'm trying not to play, too much, right now. Life's funny sometimes, unless I get into crying about it.

michaeloceanmoon
12-01-2012, 08:13 PM
Not sure why I keep posting this message twice. Anyway just a post fart here. Apologies!

Pippin
12-02-2012, 01:11 AM
I would change the strings. I recently had a situation where I was drastically out of tune and putting fresh strings on solved the problem.

^^^ This.

Sometimes intonation issues can be attributed to a bad set of strings. It does not happen all that often, but, standard deviation sometimes gets the best of tuning.