Intonation needed I think

[JackH]

Hey guys,

I have an Ibanez Artwood acoustic electric guitar. I've played it off and on since 2003 without any problems that I have known about or realized. Now I think the intonation needs to be setup. I lowered the action a month or two ago. That went extremely well. I don't know if that changed the intonation but I've read that sometimes it does. Or, the intonation may have been off all along. I have a tuner that clamps onto the head of my guitar. I took two pictures indicating the reading when I played the low E open and then when I play the harmonic on the 12th fret. I'd appreciate your opinions on this. Is the intonation off? If so how much? I'm considering buying some blank saddles and filing them in an effort to get the guitar set-up. The only things I might change is truss rod adjustment (which is ok I think) or filing a new saddle to adjust the intonation. I haven't shopped yet but I hope I can find some extremely cheap saddles to practice on before trying it on a better quality saddle. BTW, what is the difference I might hear from different saddle materials? Right not the one is on the guitar that came from the factory. It looks like plastic but I don't know for sure. I wanted to lower the action a month ago or so. I removed the saddle and found 3 shims under it. Two were white and one was clear. The clear one was thinner than the other two. I emailed Ibanez about the shims. They replied they don't normally put shims in a new guitar. I bought the guitar as new at a music store in AL. If Ibanez doesn't put shims in new guitars they were added by someone at the store or it was a used guitar. Anyway, I removed the shims and sanded the bottom of the saddle because it wasn't flat. The guitar plays much better now but I want to get the intonation better. Anyway, here are pictures of my tuner readings.

This looks like the harmonic is lower. I think it shows the 6th string harmonic as a sharp D.

Low E played open:


12th fret harmonic played on low E:


The A string harmonic: Harmonic indicates a flat B.
The D string harmonic: Harmonic indicates a flat E.
The G, B and high E string: I get no reading at all on the tuner on these 3 strings when fretting the 12th fret nor when I play the harmonics. What could this mean? The tuner is a Fender FT-004. Compared to others like it it is one of the cheaper models. Wait a second.

I also got a free tuner from Guitar Zoom that clamps to the head. This tuner does the same thing regarding the high 3 strings. No reading at all. However, the 3 bass strings show that the intonation is good. When I fret or play harmonic on these 3 strings they read the same as the strings played open. So I used the tuner on my Fender Mustang 1 amp. All of the strings appear to be in tune when played open as well as when I play the 12th fret harmonics. This makes me think the tuners that clamp to the guitar head are good for open strings but maybe aren't sensitive enough for the harmonics at the 12th fret. I may be wrong. I saw a video of someone setting up an acoustic and he used a "strobe tuner". Are they more accurate?

I paid less than $10 for the Fender tuner and the Guitar Zoom tuner was free except I paid shipping. Any info or suggestions on electronic tuners? At a local music store and on the inet I see a huge range of prices. But never using one before I don't know if the more expensive ones are worth it to me. So far for just tuning my guitar the ones I have seem fine.

Any help or information on this is appreciated and I thank in advance.

Jack

[Imbler]

You don't check intonation by playing 12th fret harmonics as that is totally independent of the frets. And...if that gave you out of tune results, you have bad strings or the tuner is reading some partials.

You check intonation by playing fretted positions. So if you want to check open versus 12th fret, you need to actually play the fretted note and compare its tuning to the open string,
Mike

[mc1]

Originally Posted by Imbler

You don't check intonation by playing 12th fret harmonics as that is totally independent of the frets. And...if that gave you out of tune results, you have bad strings or the tuner is reading some partials.

You check intonation by playing fretted positions. So if you want to check open versus 12th fret, you need to actually play the fretted note and compare its tuning to the open string,
Mike

welcome to the forum, nice first post!

yes jack, the open string is tuned to a note, E in this case, and the 12th fret harmonic is dividing the string in half. so physically the 12th fret harmonic is double the pitch of the open string.

as mike wrote, maybe it's the string, or maybe the tuner, but those notes by themselves don't indicate anything about the intonation.

maybe also have a search for threads on tuners, as they are often discussed and you might turn up a lot of recommendations.

[JackH]

THANKS GUYS! I'm going to go over the videos or articles where I think I heard to use the harmonic. Maybe I misunderstood. I did wonder about that though because when fretting the 12th (or any) fret you stretch the string a tiny bit by pushing it down. That would increase pitch even if just a tiny bit. But being accurate with that seemed more accurate to me. But at my level of knowledge (almost none) I know I'll get the wrong idea sometimes before I know the truth.

I'm still getting my mind blown because of how much easier it is to get info now via the internet. When I was younger I'd have to go to a library for most information. Now I can get much more and don't even have to stand up. Much less get in the car and go somewhere.

Thanks again guys,
Jack

[mc1]

you do use the harmonic, but you compare the pitch to the fretted note at the 12th fret. you are also correct that fretting the string stretches it and throws off the pitch. to compensate for that the saddle is moved back just slightly to lengthen the string. i'm not an expert on any of this, however.

but first you need to sort out the tuner/string issue, i'd say.

and keep watching videos and reading, as you mention it's amazing the amount of information out there. but beware, a lot of it is not quite correct because it's from people who just know enough to be dangerous, like me.

[John Arnold]

I did wonder about that though because when fretting the 12th (or any) fret you stretch the string a tiny bit by pushing it down. That would increase pitch even if just a tiny bit.

That is why the saddle is compensated by moving it further from the nut. Increasing the length lowers the pitch.
The saddle angle is part of this compensation, because the thicker strings increase in pitch more as a result of fretting.
The reason saddles have staggered compensation is because there is no straight line that will produce perfect intonation on all strings.

[JackH]

Originally Posted by mc1

you do use the harmonic, but you compare the pitch to the fretted note at the 12th fret. you are also correct that fretting the string stretches it and throws off the pitch. to compensate for that the saddle is moved back just slightly to lengthen the string. i'm not an expert on any of this, however.

but first you need to sort out the tuner/string issue, i'd say.

and keep watching videos and reading, as you mention it's amazing the amount of information out there. but beware, a lot of it is not quite correct because it's from people who just know enough to be dangerous, like me.

The strings are Elixir light gauge and 2 weeks old at the most. I'm sure how much play has more impact on their life than time. I play 2 or 3 hours a day or so. But they are still sounding good (to me) and they are staying in tune. I normally change strings when they start sounding dull or going out of tune sooner than new ones do. I try to leave a set on the guitar as long as they aren't too bad just to save money. I don't perform so the strings sounding "not completely crisp" isn't a big deal. Anyway, when I do change them I'll do more intonation checking to see what I see with new strings.

I will research tuners also. So far the ones I have now are perfectly fine for my needs. Having said that I do like to have really good tools or equipment for whatever I'm doing. Sometimes that means spending money on something I don't absolutely need just because I want higher quality. I'm sure I'm the ONLY ONE to do that. Yeah right.

Thanks again,
Jack

[JackH]

Originally Posted by mc1

That is why the saddle is compensated by moving it further from the nut. Increasing the length lowers the pitch.
The saddle angle is part of this compensation, because the thicker strings increase in pitch more as a result of fretting.
The reason saddles have staggered compensation is because there is no straight line that will produce perfect intonation on all strings.

With learning more about this I've had a few thoughts. First is why not have saddles on acoustics like electric guitars that you can adjust with a screw? Or are there some like that? Also, I have one saddle for all 6 strings as do most acoustics I've seen. But I have seen guitars with two saddles. One for the 4 bass strings and another for the two high strings maybe. I think I've seen that in pictures of guitars. I had a Sigma acoustic many years ago and I had a tech put in a pickup. It was just the pickup under the saddle and a connector. No preamp or controls at all on the guitar. When I got the guitar back the guy had cut the saddle in half between strings 3 and 4. When I picked the guitar up the tech wasn't there and the guy that was there didn't know anything about why he did it. I never did call back to ask why. I assumed there was a good reason. Why can't a six string have 6 separate saddles, one for each string? I'll bet someone somewhere has been filing a new saddle and filed too much on the last string. Then the entire saddle may need to be trashed. I wonder about this because I don't know anything about it. But I'm sure there is a reason they are done like they do it for some reason. Better sound maybe?

Jack

[Lakedaisy]

Heres a method used by a fairly trusted guy (Frank Ford) in the guitar business.

http://www.frets.com/FretsPages/Luth.../compcalc.html

[JackH]

Originally Posted by Lakedaisy

Heres a method used by a fairly trusted guy (Frank Ford) in the guitar business.

http://www.frets.com/FretsPages/Luth.../compcalc.html

What do you use to measure CENTS?

He starts his work by measuring from the nut to the 1st fret. Shouldn't the distance from the inside of the nut to the center of the 1st fret be the same distance? It's the same on my guitar for all strings. I measured it. The distance from the nut to the center of the saddle at the 6th string is 25.5". So I guess my fret scale length is 25.5" The other strings have slightly different measurements.

My guitar has a fret scale of 25.5", measured at the 6th string. To follow the procedure in that article do you measure the distance on each string? Does each string have a seperate "fret scale" length to use in his math equation? The difference between the length of each string on my guitar seems like it would be less than the "margin of error" he uses. I'm sure I'm missing something here.

Jack

[Alan Carruth]

"First is why not have saddles on acoustics like electric guitars that you can adjust with a screw?"

It would weigh too much. On a solid body you want plenty of mass and stiffness at the saddle to keep the energy in the string from 'leaking' out into the top and cutting into the sustain. On an acoustic if all the energy stayed in the string you wouldn't hear anything. The top and bridge have to be kept light to produce sound.

"I had a Sigma acoustic many years ago and I had a tech put in a pickup. It was just the pickup under the saddle and a connector. No preamp or controls at all on the guitar. When I got the guitar back the guy had cut the saddle in half between strings 3 and 4. When I picked the guitar up the tech wasn't there and the guy that was there didn't know anything about why he did it."

Under saddle transducers work by converting pressure changes at the bottom of the saddle into electrical signals. Ideally both the bottom of the saddle and the slot have the be really flat for all the strings to work well. It's possible that one or the other, probably the slot, was not quite flat on that guitar. It also sometimes happens that string tension pulls the top up a bit, causing the bridge to bend upward in the middle, which can cause the two E strings to drop out as the pressure is removed from them. At any rate, in cases like that the quick and dirty (and sometimes the ONLY) fix is just to cut the saddle into sections so that it can follow the shape of the slot.

"Why can't a six string have 6 separate saddles, one for each string?"

Some people do that. I've seen bone pins that screw in, which makes adjusting the action for each string a snap. Why don't we all do it that way? Tradition...

"What do you use to measure CENTS?"

Many tuners will indicate cents. Usually the ones with a needle-type gauge, either digital or analog, will have a scale calibrated in cents above and below the 'correct' pitch. There are 100 cents in a semitone, so when the needle goes above 50 cents sharp the tuner will usually shift up to the next semitone, and the needle falls the the other end of the scale indicating cents flat.

This is handy to know when you're adjusting intonation. Suppose the distance from the 12th fret to the 13th is 16mm. That means that for a string that length changing the saddle position 1.6mm (a bit more than 1/16") will result in a pitch change of about 10 cents. If the note is off by 5 cents, you need to move the saddle whichever way by about 1/32". This gives you a quick way to get most of the way there, and also a way to judge whether there's enough adjustment available to actually do the job.

"He starts his work by measuring from the nut to the 1st fret. Shouldn't the distance from the inside of the nut to the center of the 1st fret be the same distance? It's the same on my guitar for all strings. I measured it."

Right. He's probably just making sure the nut's in the right place.

"The distance from the nut to the center of the saddle at the 6th string is 25.5". So I guess my fret scale length is 25.5" "

No. It's overwhelmingly likely that some compensation for string stretch has already been built in, so the saddle is probably further back than the theoretical distance that was used to calculate the fret placement. OTOH, the distance from the front edge of the nut to the center of the 12th fret is (usually) exactly half of the scale length (unless the nut has been compensated as well).

At this point I'll stop lest I confuse you even more. There's a lot more to the whole subject of intonation than there 'ought' to be, and in the end it's more or less futile anyway. It's almost impossible to make an acoustic play 'in tune' on every note on each string, and even then you're still dealing with Equal Temperament, which is out of tune anyway in a sense.

[mirwa]

A very good post alan,

For those that got confused, it only just starts to scratch the surface of guitar intonation

Steve

[Imbler]

[QUOTE=mc1;4748882]welcome to the forum, nice first post!

Thanks for the welcome; I've been reading this forum for a little while, and have enjoyed learning a little about steel strings, as I build classicals. They are very similar and very different!
Mike