Saddle for Low G Uke

[Prenez]

a few basic questions for a newbie:

1 are saddles filed lower one one side than the other? uninformed common sense might suppose that the side with a low g would be filed lower, because thicker string, and you want all the strings to be in the same plane.

2 are saddles shaped differently for a low g instrument than a high g instrument?

seems to be different for different instruments too. The saddle on my kamaka concert L appears to be even; the saddle on my Martin Tenor is curvy and dippy.

 

[merlin666]

Do you mean bridge or saddle? The saddle is a small piece that is inserted in the bridge and the strings pass over it. The bridge anchors the strings. Some saddles are just straight pieces and work well, and others have adjustments for single strings called compensation if intonation needs improvement. Low G is often thinner than the C string and some people change saddle height to suit their taste.

 

[Prenez]

I mean the saddle, thanks. Why would the Low G be thinner than the C? In my case, it's not. I use flurocarbon for c e a, but a wound string for the low G

 

[LorenFL]

The Low G string is fatter (even if it's wound) and vibrates at a lower frequency, and very likely a higher amplitude. That means that in addition to being fatter (making it closer to the frets), it's also MOVING more, meaning that it could be more likely to buzz against a threat.

So, by that logic, I would expect that your Low G action should be slightly higher than, say... your A or E string.

I don't think your fingers would notice the difference in height from one string to another. But, if your action was already really close, and you made it LOWER to make a fatter Low G string level with the other strings, it could introduce a fret buzz.

That's action height (mostly adjusted at the saddle, but can also be adjusted at the nut). The other aspect, as Merlin mentioned, is intonation. If your uke had perfect intonation with a high G, then going Low G will likely throw it off because the actual frequency of the note is very different. (392 Hz vs 196 Hz)This gets complicated, but if you can wrap your head around it, it's not that difficult.

If your perfectly tuned string plays within 5 cents of correct at the 12th fret, then the intonation at the bridge is correct. If it's sharp, then you need to make the string longer by moving the contact point of the bridge away from the nut. If it's flat, then move it the other way.

If the 12th fret is okay, then check the first 3 frets. If it's going sharp on the first few frets, it could mean that the action at the nut is too high, requiring too much string movement to fret the note. Or, it could be that the nut needs to be adjusted for intonation similar to the saddle.

Chasing perfect intonation can be challenging. Getting it "close enough" isn't too bad unless you have a really crappy uke. I spent a lot of time searching for what "close enough" would be, and nobody really gives a good answer. I think within 5 cents across the whole fretboard is excellent and may or may not be attainable. Getting within 10 is probably good enough for most ears.

And you can experiment with tuning a string a few cents sharp or flat to make it better further up the string. (rather than starting with a perfectly tuned string and having it be 12 cents sharp at its worst, tune it 6 cents flat and it will be "pretty close" everywhere)

YMMV. Have fun!

 

[merlin666]

I mean the saddle, thanks. Why would the Low G be thinner than the C? In my case, it's not. I use flurocarbon for c e a, but a wound string for the low G

That is likely an exception with very thin fluorocarbon strings. With Nylon and Nylgut strings a wound low G is often almost as thin as A string and the C and E are thickest, therefore saddles are sometimes slightly higher in the center even if fretboard is not radiused.

 

[LorenFL]

Replying to this thread, plus having just restrung my uke and been talking about that, inspired me to work on the action and intonation of my uke!

I abhor wound strings, so what I have is Low G with solid strings. Basically, the thinnest fluorocarbon strings I could find.

Every uke is different, but I was able to get the intonation nearly perfect with just standard action adjustment and a little bit of work on intonating the saddle. I'd resisted doing this for over 2 years because a) It's the nicest uke I've bought, and I didn't want to mess it up (yeah, I know saddles and nuts are easily replaced), and b) it was SUPPOSED to have been professionally set up by Mim when I bought it. I've been putting up with crappy intonation on the G string since I bought it!

So, I first pulled the saddle (pro tip: Put something under the strings and slide it towards the bridge and you can probably slide the saddle out without having to remove or even loosen the strings) and lowered the action at the 12th fret to around 2.5mm.

From there, I found that the 12th fret intonation was sharp on C, a little more sharp on G, VERY flat (23c) on E and a little less flat on A. I played with placing a toothpick in front of the saddle to verify that I was moving things in the right direction. Shorter string for the flat ones. And it almost didn't seem like I was going to be able to get far enough with a standard saddle! (but, my toothpick was raising the action, which threw off my perspective)

Pulled the saddle again, and filed the angle of the top such that G and C were contacting further from the nut (longer string to make those less sharp), and the E and A strings closer to the nut (shorter string to make those less flat). I went all the way with both adjustments. I can't do more without making some kind of a custom saddle. Worthy of note, this uke came with an round-top uncompensated saddle. I slipped it in upside down so that I could use the flat side as a basis for the intonation adjustment.

Fortunately, that was enough. Well, it depends on how you look at things. But, if I give the 12th fret JUST enough pressure to get the note, the intonation is nearly perfect. I never play up there, anyway, so it's close enough.

Next step: check the first few frets. Lowering the action at the saddle helped that a lot, too. It's closer than it's ever been. But, still off. So, I measured the action at the first fret, aiming for about .5mm. There was a bit more than that. I used a folded sheet of sandpaper to deepen the slots. I took the G string as low as I dared. The other strings didn't need as much, but I took them all down some.

Now, intonation on the first 3 frets is within 5c, again with a light touch. I'm pretty happy with it. I thought I was going to have to get creative with nut compensation, but it's not needed.

I'm going to tune everything about 2c flat so that when I strangle chords, they won't go too sharp. Should end up sounding a lot better than it ever has (and I've actually really enjoyed how this uke sounds over the past 2 years!), and the lower action is definitely easier to play.

Hope you have similar luck! If you're worried about adjusting your saddle or nut, just order a set of replacements to have on hand just in case you take something too far. Or, for the nut slots, you can always do the super-glue and baking soda trick.