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Joe90
09-28-2012, 10:49 AM
Hi guys, picked up my makala mk-s (soprano) uke again today after a while out of action and tuned it back up etc. Now wanted to know the causes of intonation, namely sharp on all strings by maybe 25-30 cents when fretted. The action has been lowered at the saddle and is around 3.5mm high at the 12th fret. I havent touched the nut end as by what ive read on here it seems a good height. Still using tandard strings (awaiting martin m600s), the distance from the nut to the 12th fret is 17.4cm as is the distance from 12th fret to the saddle. Any ideas?

Pondoro
09-28-2012, 12:01 PM
I'll bet it gets progressively sharper as you fret up the finger board? True?

If it does you need to lengthen the distance from the 12th fret to the "break-over" point of the saddle. This is called "compensation."

If all of the fretted notes are equally sharp or if the 1st fret is worst and things then get better I'd investigate lowering the nut a bit. But one time the nut to 1st fret distance was wrong on a uke of mine and that made the first fret worst and everything got better from there.

Joe90
09-28-2012, 12:18 PM
Its roughly the same throughout the fretboard all up toward the 12th. Do you think i should lower the nut a little? I have around a 2mm gap at the first fret and the strings, how low should i be aiming for as im worried it may buzz? Should i sand the frets too afterward? Thanks for the input.

OldePhart
09-28-2012, 01:10 PM
2mm at the first fret is VERY high and almost certainly the cause of your problems. Ideally, you shouldn't be able to slip much more than a business card between string and fret at the first fret.

As you bring the slots down you will find that the intonation starts getting better up the neck but is still dismal at the first couple of frets until you finally get the slots low enough to not pull sharp at the first fret. It can be done - and in fact an instrument that pulls sharp at the first fret by any measurable amount should be frowned upon (though most factory ukes will, in fact, pull sharp until they are set up). Unfortunately, as you begin to bring the nut slots down you may hit the point where the strings start buzzing before you get the magic intonation - especially since you have already lowered the bridge end.

One should always start at the nut, get the action low enough for proper intonation at the first fret, then work the action down at the bridge end. If worst comes to worst you may have to level the frets but once you do that and get the nut lowered enough you'll be amazed at how much better it sounds and how much more easily it plays.

Here is a series I did on setting up a Dolphin, the only ukulele I've ever had to level the frets on - http://www.youtube.com/playlist?list=PL0AEA7587C5D93985&feature=view_all

John

Mim
09-28-2012, 02:19 PM
Sometimes it is just strings that have overstretched. i always say first to change the strings. It is the easiest/quickest fix and usually will solve it about 80% of the time.

mm stan
09-28-2012, 03:17 PM
Yup put a new set of strings on first and eliminate the cheapest and easiest alterative... if not extend the scale by working on the saddle...Good Luck

webby
09-28-2012, 04:50 PM
I'd be replacing the strings before I did anything else.

Joe90
09-28-2012, 07:35 PM
Ill start on the strings first then, if that doesnt yeild results ill then lower the nut end. Very good vid john.Thanks for the help people.

Pondoro
09-29-2012, 01:38 AM
I agree with all the advice above. I would not suspect the saddle placement since the problem does not get worse as you move up the neck. Work at it until you get it right, you are learning a useful skill.

Joe90
09-29-2012, 03:11 AM
Strings have been changed and im forever retuning, cant wait for them to settle. Intonation is now pretty much spot at the 12th fret on all strings, maybe a little flat on 1 or two strings but not enough to worry me. This may settle with the strings?

Pondoro
09-29-2012, 04:06 AM
Excellent. As you play longer and play different and more expensive ukes often your standards change, don't be afraid to revisit this in six months or a year.

OldePhart
09-29-2012, 08:58 AM
Excellent, but I'd check that intonation around the first and second fret. If there really is 2mm between the strings and the first fret I can't imagine the intonation being correct there. I've been wrong before (once back in '68 I think it was) but that's really high at the first fret - in fact, it's more in line with what I'd expect at the 12th fret.

John