Guitar Intonation Problem

**mambosun** · 03-14-2011, 06:51 PM

I need advice from you experts!

I recently asked my luthier to swap the stock TOM bridge of my Jazz box for a rosewood one.Strings are Thomastik 13/53.
I Like the sound much more and the intonation was OK, so very happy !

After extensive playing I lately found the intonation has slightly changed and after carefull checking it with a tuner, both high E and B strings are now slightly out of tune: the B is a bit closer to C and E to F (actually less than half tone) when I press string at the 12th fret, and compared to their relative harmonic overtone. Other strings have no intonation problem.
So my question: is it something I quite easly fix myself and how to proceed, or do I have to send back my guitar to the luthier?

**SamBooka** · 03-14-2011, 06:56 PM

I cant answer this question, only add this comment.

I dont understand how people get 6 months out of a set of strings (TIs included) since after about 8 - 10 weeks of 1hr/day playing my bridge looks like this..

**NiAg** · 03-14-2011, 07:25 PM

Mambo,

Respectfully, if you are asking these very basic questions, then I suspect that it will be a fairly long exercise to get this sorted out yourself.

Bridge compensation is not a complex thing, but you may be happier in the end to have some hands-on help in getting the results you want.

**mambosun** · 03-14-2011, 07:59 PM

Originally Posted by NiAg

Mambo,

Respectfully, if you are asking these very basic questions, then I suspect that it will be a fairly long exercise to get this sorted out yourself.

Bridge compensation is not a complex thing, but you may be happier in the end to have some hands-on help in getting the results you want.

Thanks for your quick answers.
My question was : would I have it solved by just slightly moving/tilting the bridge or is it anything more serious than this?

**barrymclark** · 03-14-2011, 09:22 PM

I play my strings until they don't hold intonation anymore. haha.

I play about one hour a day. They tend to last me about 4 to 6 months before they get where they don't hold their intonation.

If you've played the strings long enough, you just may need a string replacement.

If that isn't it, it is entirely possible that your bridge has come slightly askew.

If that isn't it, then you may have an off cut on your rosewood bridge.

Intonation is a dance of many things.

**barrymclark** · 03-14-2011, 09:24 PM

Originally Posted by SamBooka

I cant answer this question, only add this comment.

I dont understand how people get 6 months out of a set of strings (TIs included) since after about 8 - 10 weeks of 1hr/day playing my bridge looks like this..

I am one of those! haha. I play with an extremely light hand. My hand never truly rests on the strings but will only muffle strings for whatever end by touching them but no real weight is applied. For whatever reason, the way I play keeps the bridge in place until I drop it. haha.

**NiAg** · 03-14-2011, 09:41 PM

>>> would I have it solved by just slightly moving/tilting the bridge or is it anything more serious than this?

Ah, OK.

Maybe.

If your strings are a mess (worn, bent, dirty - dirty being by far the most common problem) then no, repositioning the bridge will not help.

Even if some players find that they can limp along with wrecked strings by moving the bridge, I have found that the inconsistency of wrecked strings is a bigger problem that can be compensated by moving the bridge.

If you only check the 12th fret, then you can fool yourself that moving the bridge has worked with old damaged, or dirty strings.

If your strings are fine, then moving the bridge will work assuming the bridge was made reasonably well for the strings you use. (This mostly means that if you use a plain G, the bridge should be cut to deal with this.)

Start with the high E at 1,5 mm more than the measured scale length (2X the front of the nut to the CENTER of the 12th fret), and the low E about 2,5 to 3,0 mm more than the scale length.

Then fiddle as needed to get a decent "best fit" for overall intonation.

All in my opinion.

**mambosun** · 03-15-2011, 11:28 AM

Originally Posted by NiAg

>>> would I have it solved by just slightly moving/tilting the bridge or is it anything more serious than this?

Ah, OK.

Maybe.

If your strings are a mess (worn, bent, dirty - dirty being by far the most common problem) then no, repositioning the bridge will not help.

Even if some players find that they can limp along with wrecked strings by moving the bridge, I have found that the inconsistency of wrecked strings is a bigger problem that can be compensated by moving the bridge.

If you only check the 12th fret, then you can fool yourself that moving the bridge has worked with old damaged, or dirty strings.

If your strings are fine, then moving the bridge will work assuming the bridge was made reasonably well for the strings you use. (This mostly means that if you use a plain G, the bridge should be cut to deal with this.)

Start with the high E at 1,5 mm more than the measured scale length (2X the front of the nut to the CENTER of the 12th fret), and the low E about 2,5 to 3,0 mm more than the scale length.

Then fiddle as needed to get a decent "best fit" for overall intonation.

All in my opinion.

My strings are new, flatwound Thomastik Jazz Swing Series JS113
Thanks for your informative reply, I will check this.

**FatJeff** · 03-15-2011, 12:01 PM

Originally Posted by SamBooka

I cant answer this question, only add this comment.

I dont understand how people get 6 months out of a set of strings (TIs included) since after about 8 - 10 weeks of 1hr/day playing my bridge looks like this..

When you say "your bridge looks like this," do you mean it's slipped out of position by itself? Or that your strings are so old that you have to do that to your bridge in order to make the intonation good?

**mambosun** · 03-15-2011, 12:23 PM

Hi FatJeff,
Did you notice this slight intonation issue with your JZ4?
Do you use the rosewood or TOM bridge ?

**SamBooka** · 03-15-2011, 12:28 PM

Originally Posted by FatJeff

When you say "your bridge looks like this," do you mean it's slipped out of position by itself? Or that your strings are so old that you have to do that to your bridge in order to make the intonation good?

That is how I have to position the bridge to get it close to in tune.

I change the strings and put it back where it belongs (in the pic you can see where the old bridge sat originally) After about 2 weeks I start tweaking to get the intonation right. This means moving the bass back a little. The bridge is not getting knocked out of place.

It seems worse on my EmpReg than on my 125/165 but I figured that was due to the longer scale length.

**FatJeff** · 03-15-2011, 01:08 PM

Originally Posted by SamBooka

That is how I have to position the bridge to get it close to in tune.

I change the strings and put it back where it belongs (in the pic you can see where the old bridge sat originally) After about 2 weeks I start tweaking to get the intonation right. This means moving the bass back a little. The bridge is not getting knocked out of place.

It seems worse on my EmpReg than on my 125/165 but I figured that was due to the longer scale length.

The reason I ask is that I have the exact same issue with my Godin 5th Avenue Kingpin. The strings I've got on there are pretty old (at least 6 months), and this made me think that all I have to do is change the strings instead of getting the thing set up. I'll try that tonight and see how it goes.

**ejwhite09** · 03-17-2011, 01:47 PM

I remember Steve Cropper saying in an interview he changed his strings when they broke. Then I read Eddie Van Halen changes his every show! Certainly there's a happy medium. But in my book as long as a string stays in tune, no need to replace it. Sometimes they go 'dead.' Sometimes they kind of wear in and sound warmer. Really depends on the string(not the brand).

I'd just try to intonate it by using the bridge and tuner method. It is super easy, I do it on my mando, NEED to do it on my Godin. It can be a hassle but I'd say if you can intonate it, then its fine.

I have a Godin 5th avenue, non electric model, honestly, its probably the most 'in tune' guitar I have and that includes a Gibby LP.

EDIT:
I just realized there may be some confusion saying the Godin is the most in tune guitar I have and then saying I need to intonate it. I need to because I dropped it from about chest height onto a hardwood floor....it landed on its top, I was thinking catastrophic loss, bridge snap or punched through the top, nope, just needs its bridge adjusted and it broke a string. And I've found my new travel guitar out of the ordeal...I reckon the airlines really can't abuse it anymore than that.

**mambosun** · 03-20-2011, 09:56 AM

Originally Posted by NiAg

>>> would I have it solved by just slightly moving/tilting the bridge or is it anything more serious than this?

Ah, OK.

Maybe.

If your strings are a mess (worn, bent, dirty - dirty being by far the most common problem) then no, repositioning the bridge will not help.

Even if some players find that they can limp along with wrecked strings by moving the bridge, I have found that the inconsistency of wrecked strings is a bigger problem that can be compensated by moving the bridge.

If you only check the 12th fret, then you can fool yourself that moving the bridge has worked with old damaged, or dirty strings.

If your strings are fine, then moving the bridge will work assuming the bridge was made reasonably well for the strings you use. (This mostly means that if you use a plain G, the bridge should be cut to deal with this.)

Start with the high E at 1,5 mm more than the measured scale length (2X the front of the nut to the CENTER of the 12th fret), and the low E about 2,5 to 3,0 mm more than the scale length.

Then fiddle as needed to get a decent "best fit" for overall intonation.

All in my opinion.

I slightly tilted the "Hi E" portion of the bridge 4-5mm away from the headstock and the Low E portion kept at the same position and it works.

I guess using a compensated bridge matching closely my set up would allow a perfect horizontal bridge but the bridge angled like this does'nt look too weird.

**NiAg** · 03-20-2011, 11:48 AM

Yes, you can square-up the bridge base via a compensation on the saddle. But I see not particular reason to do this. I am happy to let my own bridge bases fall where they work best.

**bass2man** · 03-20-2011, 02:14 PM

What kind of guitar do you have? I assume it is not an archtop as these usually have rosewood or ebony bridges anyway...

I have changed the TOM on my Tal Farlow to a rosewood bridge as I wanted to mellow out the sound some..one thing that is more critical for intonation with a rosewood bridge is that the feet are perfectly flush and exactly match the curve of the top of the guitar...required for good intonation...not so critical with a TOM as you can adjust for that...it may look flush, but the feet may fall of slightly in the front of the bridge (or back or the tips or heels) and can impact intonation..

You may want to ask your luthier if he did that...just a thought..

**NiAg** · 03-20-2011, 02:59 PM

Can you explain how the base-to-top fit affects intonation, and how such a misfit would be compensated with a t-o-m bridge, but not a wooden bridge?

In my opinion, a good fit between the base and top is rather important for a few reasons, but intonation is definitely not one of them.

Also, having a t-o-m bridge does not have any practical impact whatsoever on the benefits of a good base-to-top fit - in my opinion.

**pingu** · 03-20-2011, 06:06 PM

one thing that is more critical for intonation with a rosewood bridge is that the feet are perfectly flush and exactly match the curve of the top of the guitar...required for good intonation

thats not true ............

**NiAg** · 03-20-2011, 06:57 PM

Ping,

While I agree with you that the base-to-top fit does not directly affect intonation, it is possible that there is something interesting to kick around on the subject that bass2man raises.

It is also possible that bass2man may have simply worded something differently than we might expect.

**mambosun** · 03-20-2011, 07:35 PM

Originally Posted by NiAg

Yes, you can square-up the bridge base via a compensation on the saddle. But I see not particular reason to do this. I am happy to let my own bridge bases fall where they work best.

Except for cosmetics reason I agree with you.

**pierre richard** · 03-20-2011, 08:22 PM

My strings are eight years old...I am serious...now that is old...

I am just now to a point where I need to change them because of intonation issues....

My Ibanez is a 1977 2355 (es-175)...thomastik 014 flatwound...and are eight years old...

Like cropper said..I do not change them unless they break...I have never broken a string on this guitar and I have had it since 1978...

time on the instrument...pierre..

**bass2man** · 03-21-2011, 09:15 PM

I see your point..."required" is too strong a word here..."just one thing that may impact intonation" is probably better...I stand corrected...

My point was that if the top foot is square and the bottom foot of the bridge is not..say falls away at the front of the foot facing the fretboard, that side of bridge MAY lean forward slightly, possibly impacting intonation..at least for the top strings which seems to be the issue in the OP.

I have an archtop which was a little "off" up top on the high strings...I noticed there was a little gap in the front of the lower foot of the bridge...had it reshaped to the top and it seemed to fix it..