Tuning issue

[Sandoz64]

Hi all, I just got my first mandolin. Ibanez semi acoustic. I have an issue with tuning. When I get it tuned on open strings all good. When I play on the fifth fret of the g strings it is almost a full semi tone sharp. The other strings are ok up the neck, not perfect but playable. The g isnt behaving anyiwher after the 3rd fret though. I tried moving the bridge around but it mde no difference. Any suggestions on how to get the g playing true? Thanks.

[OneChordTrick]

Think that you need to persevere with adjusting the bridge. Some useful tips here https://www.mandolincafe.com/forum/s...tonation-right.

When you fret on the 12th fret the note should be an octave higher than the open string. If it’s sharp then you need to move the bridge away from the nut. If it’s as sharp as you say at the 5th fret you’ll have to move it some distance, at the 12th it will be about a tone sharp so you’ll need to move it almost the distance between the 11th and 12th frets.

If it’s a new instrument set up may not have been perfect from the start or it may have moved in shipping.

[allenhopkins]

That kind of discrepancy -- the fourth strings a half-tone sharp at the fifth fret, the other strings perhaps a little sharp but acceptable -- suggests more that bridge location. Perhaps your bridge saddle is reversed, and the compensation -- notice that the saddle's not "straight across," but divided into segments, with different string courses slightly closer or more distant in relation to the nut -- is backwards. Here's a thread with pictures of what your compensated bridge should look like. You can fix this just by reversing the saddle's position on top of the bridge.

Otherwise, have you checked to see if the G strings aren't hitting the sixth fret, when you fret them at the fifth? A twisted neck, a high sixth fret, or too-low action on the "bass" side can cause that. Do the G strings "rattle" or buzz when fretted at other frets?

And, of course, are you using the strings the Ibanez came with? Inexpensive Asian instruments can arrive with inferior strings, and if yours didn't pass through a reputable dealer, there may have been no set-up before you got it. If you can't fix the problem with bridge tweaking, I'd advise a trip to a good repair shop, for at least a diagnosis and estimate.

[DavidKOS]

That kind of discrepancy -- the fourth strings a half-tone sharp at the fifth fret, the other strings perhaps a little sharp but acceptable -- suggests more that bridge location. .......

Otherwise, have you checked to see if the G strings aren't hitting the sixth fret, when you fret them at the fifth? A twisted neck, a high sixth fret, or too-low action on the "bass" side can cause that. Do the G strings "rattle" or buzz when fretted at other frets?

And, of course, are you using the strings the Ibanez came with? Inexpensive Asian instruments can arrive with inferior strings, and if yours didn't pass through a reputable dealer, there may have been no set-up before you got it. If you can't fix the problem with bridge tweaking, I'd advise a trip to a good repair shop, for at least a diagnosis and estimate.

Words of wisdom here - sure get the bridge set up correctly but make sure you check all the frets, strings, nut, nut slot height, etc. - and strings.

One additional thing - some mandolins I've worked on have had fingerboards with somewhat inaccurate fretting, so that's rare, but possible. Most of the new cheap Asian mandolin have fairly accurate CNC machine fret slots.

[Mandoplumb]

Allenhopkins is the only one that addressed the problem as one string. If the bridge is out all strings would be out. If you have a compensated bridge, not straight across or back forward back forward symmetrical then I think it's on backwards. If it is not a compensated bridge you need to get one. Set the bridge so the other three courses are correct or very close and if the G is out that much you have a problem with the bridge or less likely the nut. That's my opinion.

[Sandoz64]

Thanks for the ideas all. It is a compensated saddle. i’ll play around with it at the weekend. Think I’ll need to take the action down a bit too. What gauge strings do you use? I always used lights or extra lights on guitar. Any reason not to go for those on mandolin? Also, any thoughts on which brand/type are best?

[Sandoz64]

So it looks like the bridge was on back to front. Changed it over and it’s much better. Still not perfect but playable. I noticed that the hole depth foe the screw fixing the saddle to the bridge is shallower on one side than the other. This makes it impossible to lower the action on that side. Is that normal or do I need to drill the hole deeper? Thanks again folks. Appreciate the help.

[pops1]

Some saddles have the hole drilled all the way thru, I would drill it deeper. I have done this to many saddles. I usually drill all the way thru when I make one.