Inharmonicity of Guitar Strings

Construction and repair of Classical Guitar and related instruments
stevel
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Inharmonicity of Guitar Strings

Post by stevel » Fri Sep 22, 2017 2:03 am

Hello,

I'm hoping maybe someone can help me out. Even though this is a classical forum and we deal with those strings, I'm asking for electric guitar strings which I hope adhere to the same basic laws of physics.

My understanding is that guitar strings are inherently inharmonic, or at least plucking the string (instead of bowing it for example) creates some inharmonicity.

I know that inharmonicity alters the overtones making them a tad high due to the physcial mass of the string at nodes - sort of a null point that is subtracted from the string's length thus making it shorter and that overtone slightly high.

Pianists know this and tune pianos in "stretch tuning" rather than perfect 12tet.

I believe it may also be why some guitarists (like James Taylor) have come up with tunings that slightly alter some strings because their higher strings are better in tune with slightly sharp overtones of lower strings ("stretch tuning for guitar").

But, at any rate, here's my issue:

I have an electric guitar whose high E string has a really prominent octave overtone on all notes (at least I believe all as once it gets above the 12th fret they become hard to pinpoint).

Now, I have had strings on classical guitar (or acoustic, and even electric) that have a prominent overtone but usually it's on a single note (and maybe sometimes due to resonance, but other times just that string, because a string change will eliminate it).

But this is pretty much on the high E string (which is a steel 11 gauge) only, and on every single note.

It sounds "zingy" or "zzzy". It could be just the presence of this overtone, but it could also be that maybe it's more inharmonic than it should be.

I think I remember that at X scale length, a string of Y mass should have Z tension to operate effectively.

In fact, we know that on Steel String Acoustic Guitars the 3rd string is Wound because of this. Likewise, Electrics started this way - wound 3rd string - it was players in the 60s who started using plain 3rds (and much lighter strings).

I have a Fender Strat, and those have a common but little known problem with plain 3rd strings that produces a "warble" and I had read that this was due to the mass to tension ratio - basically, the string is the wrong mass for that tension at that scale length.

It produces a very "warbly" sound and the solution really is to use a wound 3rd string (or at least, maybe a different gauge plain G so that the mass to tension ratio is better).

I'm wondering if something similar is plaguing my high E (though why it wouldn't affect the B is odd, since it bother me on the G until I went to a wound string, but the B is a way different tension for the tuning).

For those of you who are familiar with Electrics, I've ruled out pretty much every other possibility - it's not fret buzz, it's not any frets, it's not the nut or the saddle, it's not the truss rod, nothing's loose inside or vibrating, etc. etc. etc. The pickups aren't too high, and so on.

It's only the high E, and it's this prominent octave (or close to it) overtone.

Now, obviously I can't put a wound E on there.

But I can go to different gauge strings.

I used to break 10s which is why I went to 11s.

But I can go up to a 12, or back down to a 10, or if they make a 10.5, I could try that - hoping maybe to find a more favorable ratio.

But I don't know what that ratio is, and what is most favorable!

So I'm hoping maybe someone here who is familiar with how different string tensions interact with the string's mass and overall scale length etc.

We know with G strings we often have to compensate the saddle for intonation, but if the string's not "warbling" (which is essentially "out of tune with itself - inharmonicity) then it's not an issue.

So how can I get rid of a prominent octave overtone on all the notes, or if it is an inharmonic octave overtone, is there anything I can do (go up or down in gauge) to get a more harmonic octave overtone if I can't get rid of it altogether?

Thanks,
Steve

Jussi
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Re: Inharmonicity of Guitar Strings

Post by Jussi » Fri Sep 22, 2017 3:06 pm

Hi Steve,

Interesting question! I’m sure there are more knowledgeable folk than I who may have more useful advice, but I have some related knowledge which may help (short answer in bold!):

Firstly, I’d double-check everything that isn’t the string. In my experience there are many other factors which may be relevant. If, for example, you detect this effect while playing through pickup / amplifier, there are a great many factors which may cause it (not just pickup height but the electro -magnetic characteristics of the pickup, and many analogous effects in the amplifier). One way would be to try a few different E strings of the same gauge / brand, or to put the problem string in the place of the B string to check for some artefact of the bridge / nut / pickup etc. I would also suggest that a combination of adjustments to saddle / nut / truss rod would eventually eliminate the effect (but who wants to change that perfect setup!)

That aside, the inharmonicity of a string is, as you rightly note, related to the physical characteristics of the string itself. The harmonic series (F1,F2,F3,F4…Fn) of an ideal ‘string’ can be calculated as Frequency of harmonic ‘n’ = (‘n’ / 2 x string length) x square root(string tension / mass per unit length)

The inharmonicity of a real string is defined by its deviation from this ideal. This deviation is the result of the string behaving not as a line (ideal ‘string’) but as a cylindrical volume which has different vibrational characteristics, not to mention any imperfections from manufacturing etc.

In characterising this deviation mathematically, we arrive at a description of the following form:

Real frequency of ‘n’ = ideal frequency of ‘n’ x square root (1 + B x n squared)

B is imaginatively named the ‘inharmonicity coefficient’ and, as we see in the equation above, as B increases the string exhibits more and more inharmonicity (becomes less and less ideal / harmonic).

B is calculated as (pi cubed x young’s modulus x radius ^4) / (8 x length squared x tension)

The factors of interest for you here are that as the radius (string gauge) decreases, B (and, thereby, inharmonicity) decreases. As tension increases, B decreases. As string length increases, B decreases. Thus, the most harmonic string is as thin as possible, as long as possible and under as high tension as possible.

In practice there are many other factors which also have an influence as well as obvious constraints on things like string length, radius and tension. I've measured harmonics which deviate both above and below the mathematical model, often on the same day!

As an interesting aside, bowed instruments don’t suffer this form of inharmonicity as energy is constantly being supplied to the system via the bow and gets distributed perfectly harmonically (though there are other imperfections which lead to imperfect harmonics)

Let me know what you discover!
Jussi

Alan Carruth
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Re: Inharmonicity of Guitar Strings

Post by Alan Carruth » Fri Sep 22, 2017 8:47 pm

A slightly different way to think about inharmonicity is that it's a function of the string's stiffness. On an 'ideal' string all of the restoring force that straightens it out when it's been displaced comes from tension(which, ideally, doesn't vary as the string is displaced or as it vibrates). As Jussi says, it's a function of the thickness of the string. A string with no diameter would have no stifness, but real strings have stiffness that varies as the fourth power of the diameter. Strings get stiffer fast as the diameter increases; that's where the numerator of his equation comes from . Thus the string acts something like a rod, and this effect becomes more pronounced as the string has te bend more in higher partials. On a wound string the stiffness that counts is that of the core; in theory, the windings don't contribute to stiffness. As he says, there are lots of things thhat get into this, not least, on an acoustic guitar, being the fact that the top and bridge move, so that the end of the string is not 'fixed' at some frequencies.

Bowed strings are a special case, as he says. The Helmholtz motion as the bow alternately sticks to the string, drawing it aside, and releases it to snap back, acts on the fundamental of the string, and locks the partials into a harmonic series; bascially anything that's not harmonic gets damped out by friction with the bow.

I don't think that's your problem, though: I suspect it's something more exotic.

We normally pluck strings somewhere other than in the center of their length. This has the effect of pulling the string slightly toward the end where it's being plucked, stretching it a little. Once the string has been released the streching effect diminishes for a while and then builds back up until, half a cycle of the transverse wave later, the string is being pulled toward the other end. This is a very small force, but it sets up a longitudinal pressure wave along the length of the string. You could think of it as analogus to a pressure wave in a long tube. The frequency of this wave is governed by the effective density of the string (including any windings), the Young's modulus of the core and the length. It's usually not very sensitive to the tension on the string; much more so with nylon than steel. Usually it's up near the seventh or eighth partial for normal strings in use.

Note that if you pluck the string exactly in the center it's not stretched in this way, and you should see no longitudinal wave. It turns out to be pretty much true. I do measure some L-wave in some cases for center-plucked strings, and I'm trying to refine my apparatus to eliminate it, or else find out the more exotic driver that would be required.

Since the force involved is so small you would think this would not be a problem. However, this mode of vibration is not much damped, so it doesn't take much input of energy for it to build up over time. This is naturally more effect ive when the L-wave pitch is close to a partial. In particular, when it's very close to the seventh partial the L-wave and the transverse wave can couple strongly. The result is that the seventh partial actually gets split into two peaks at slightly different pitches. The 'zing' you hear is the difference tone between those two peaks.

Note that the relationship between the transverse fundamental and the L-wave pitch is always the same for a given string, no matter what the length, since both are determined in part by the length. That's why the 'zing' shows up on every note on a given string, and is one on the reasons I think this may be your problem.

With wound strings you can sometimes get rid of it by twisting the string to alter the tighhtness of the windings. This changes the effective density of the string, and thus the L-wave pitch. With a plain string it's more of a problem.

Again, the rate of energy feed in is small, and the loss factor low, so the frequencies have to line up pretty exaclty for this to become a problem. That means you don't have to make big changes to elimiate it, with any luck. One thing that would work is to simply change the pitch of the string. That's a problem when you want to play with other people. Altering the string length is a way to do it, but, again, you're sort of stuck with that.

You could try getting the nut compensated as well as the bridge saddle. In many cases the stretching involved in fretting the string causes it to go sharp at the first fret, even though the open string is in tune and the nut is in the theoretically 'correct' position. Moving the nut a little closer to the frets iis equivalent to moving the frets back, and flats the pitch slightly. This affects the intonation at the bridge end as well; usually with a compensated nut you need less compensation at the bridge. The end result can alter the string length slightly, along with making your guitar play more in tune. I have not actually tried this as a solution to L-wave buzz, but it's a possibility in a case where there are not many others.

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Re: Inharmonicity of Guitar Strings

Post by MessyTendon » Sat Sep 23, 2017 3:12 am

It sounds like you need an entire setup by somebody who actually gives a darn about setup. The nut and saddle adjustments can affect it. Another interesting thing about electric guitars is that often times the neck pockets aren't exactly good...

Sometimes they require some shimming, this allows the neck to be setup at a really good angle where you can adjust the strings to have good break angle and good saddle height...Too low action especially for today's "rockers" can cause quite a buzz.

So think about the entire setup...neck pocket shim if necessary, saddles adjusted, and a new nut...if the saddle came pre-installed with a Tusq or other Graphtech product then it is likely the OEM saddle needs some manipulation.

It does sound like the nut slot is not quite right and that ringy zzz sound is from the string shaking in the nut slut. This problem is common and it gives that sitar like sound....For what it's worth you might want to take a fine grit sand paper and floss it in the slot of the nut...see if that does anything. Really lite effort.

stevel
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Re: Inharmonicity of Guitar Strings

Post by stevel » Mon Sep 25, 2017 12:24 am

Jussi wrote:
Fri Sep 22, 2017 3:06 pm
Thus, the most harmonic string is as thin as possible, as long as possible and under as high tension as possible.
This helps.

Interestingly though - and let's see if I have this right.

If the string is longer, it actually has to have more tension on it right?

So, in other words, a Les Paul with a shorter scale length (let's pretend it's the 1st fret's worth) tuned to E has to have a lower tension than a Strat with a longer scale length. IOW, if you "add a fret's worth of length" to the neck, at the same overall tension the string's going to have to be tighter to be the same pitch.

But, if I'm correct, a thinner string will have LESS tension on it tuned to the same pitch than a thicker string. For example, tuning a B string to an E pitch is going to have a lot more tension than an E string.

So don't these two counteract each other?

If so, the trick is to find which thickness has the highest tension at the lowest diameter.

Looking at the link: http://www.daddario.com/upload/tension_chart_13934.pdf

For an E string at 9, the tension is 13.1 (lbs per square inch I think).

Then at 10, it's 16.2. That's an increase of 3.1

11 is 19.6, so that's a 3.4 increase.

a 12 is 23.3 so that's a 3.7 increase.

So which is the more favorable ratio? We want more tension, but, we want thin-ness. So it actually sounds like the 9 or 8 0 it's a 2.5 increase from 8 to 9 - or do I have that backwards? The bigger increase per unit of thickness is better?
In practice there are many other factors which also have an influence as well as obvious constraints on things like string length, radius and tension. I've measured harmonics which deviate both above and below the mathematical model, often on the same day!
Our Piano Tuner has a piano tuner that measures overtones - it actually allows him to store presets for various pianos - so each and every piano is different - this allows him to do precise stretch tuning for each instrument - he recalls the memory and tunes based on that (making adjustments of course).

I imagine there are many factors...
As an interesting aside, bowed instruments don’t suffer this form of inharmonicity as energy is constantly being supplied to the system via the bow and gets distributed perfectly harmonically (though there are other imperfections which lead to imperfect harmonics)
Yes, I had heard this. I believe it's possible this may have contributed at least in part for the strings becoming the "core" of the orchestra - they played "in tune with themselves" which makes it easier for all of the members to tune to each other, and since they have not frets, can further refine to other temperaments as well.

As far as we're concerned - yes, I would believe how you pluck the string, and where, and how old it is is going to cause it to vary, as well manufacturing imperfections.

One thing I noticed with the plain G - the "warble" became more obvious to me as I kept moving to thicker and thicker gauges. I probably also became more attuned to it though...(and your other solutions - this has been a problem for me for decades - I've been through many brands of strings over the years).

I guess I'm at the point where I wonder if moving up to a 12 on the high E would give me more, or less inharmonicity, or, if moving back down to a 10, or even a 9 would improve it.

I'm also saddled (pun intended) with the issue of string to string balance and breakage - The B at the current tension is "floppy" - easy to bend a step and a half - but the high E is tough to bend that far at all. So a 10 or 9 would improve that, but, I'd be more likely to break it (which is why I went to 11s to begin with). That said, I once put a 19 wound G on, and broke it almost immediately - I think becuase it was SO much tension.

Also, the B as is is looser - under less tension because of its size (14) and doesn't warble, so I wonder if the High E being thinner would benefit.

But then I'll break it.............

stevel
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Re: Inharmonicity of Guitar Strings

Post by stevel » Mon Sep 25, 2017 12:37 am

Alan Carruth wrote:
Fri Sep 22, 2017 8:47 pm


Note that the relationship between the transverse fundamental and the L-wave pitch is always the same for a given string, no matter what the length, since both are determined in part by the length. That's why the 'zing' shows up on every note on a given string, and is one on the reasons I think this may be your problem.
Alan, my math is not as strong as yours and Jussi's, nor is my basic physics etc, but I kind of understand this - I know what difference waves are and what 7th partial means, and I know that a guitar string vibrates in sort of "half" of a cycle, and if you pluck at one end it kind of "travels down and bounces back" - a standing wave, etc. - so this kind of all makes sense to me.

I'm wondering if there are ways I can rule this out.

For example, if this is true, at pitch (E), would tuning the string to F, or to Eb impact it - or rather, if doing either of those eliminates the prominent 2nd partial (octave harmonic over the fundamental) would that definitively mean that this is my issue?

Another factor is that I play with relatively high action compared to most guitarists.

My comprehension would be that the higher the action, the more angle the string makes when you fret it - does this theoretically increase its length (becuase it has to travel further than a straight line) or tension?

I know with higher action, the string must be longer to remain properly intonated.

I have a Fender Strat so the bridge saddles are both height adjustable and "length" adjustable. Usually, as tension increases (either through thicker strings or higher action) you have to "make the string longer" to make it play in tune - so you move the saddle back which essentially increases the length of the string.

It could be that I can change the length of the string "minimally" in that if I lower the action, I can shorten the string as well. I suppose, with a thinner gauge string, it would also need to be shortened a bit.

Maybe Leo Fender really did screw up and make the scale lengths of Strats wrong - or we screwed up for using much smaller gauge strings.

Hmm....

stevel
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Re: Inharmonicity of Guitar Strings

Post by stevel » Mon Sep 25, 2017 12:49 am

MessyTendon wrote:
Sat Sep 23, 2017 3:12 am
It sounds like you need an entire setup by somebody who actually gives a darn about setup. The nut and saddle adjustments can affect it. Another interesting thing about electric guitars is that often times the neck pockets aren't exactly good...

Sometimes they require some shimming, this allows the neck to be setup at a really good angle where you can adjust the strings to have good break angle and good saddle height...Too low action especially for today's "rockers" can cause quite a buzz.

So think about the entire setup...neck pocket shim if necessary, saddles adjusted, and a new nut...if the saddle came pre-installed with a Tusq or other Graphtech product then it is likely the OEM saddle needs some manipulation.

It does sound like the nut slot is not quite right and that ringy zzz sound is from the string shaking in the nut slut. This problem is common and it gives that sitar like sound....For what it's worth you might want to take a fine grit sand paper and floss it in the slot of the nut...see if that does anything. Really lite effort.
Well, bunch of issues here.

Firstly I have taken it to two different techs, both of whom I trust and are highly regarded as "the best in town".

Secondly, the nut is an LSR roller nut which has little ball bearings the string rides on. It's possible this creates its own set of problems, but this should not affect a fretted string or if I put a capo on.

I don't like low action or buzz and have pretty high action and pretty thick strings for a rocker. It is possible the break angle over the bridge (which is a floating trem) is not ideal. One tech swapped the low and high E saddles once just to see if it was the saddle itself and problem still existed. On the advice of the other I loosened the other strings enough to "deck" the trem so the break angle over the saddle on the high E was much steeper and that didn't help.

It has been re-fretted and the neck was planed, and the luthier said he had to do quite a bit of leveling because from the factory it was all over the place. After that, the low E - F note was miles above the fingerboard. The LSR nut has some little shims under it so I took these out to get the action back down on that low F but I recall the problem existing before then.

The neck could be shimmed, as could the nut, and it could probably be really fine-tuned. I've had set ups in the past where the guitar played beautifully in tune up the entire neck however, one tech had to grind the back of a saddle to get it so it could come far enough back to intonate because I have such high action.

At any rate, maybe it's just this guitar was never intended to be played on anything but 9s with factory action.

I love the guitar, and could never afford to buy another one (or even a neck for it). I can't even keep dumping money into setups.

But it drives me freaking crazy. I could never record with it. I play it all the time at gigs - with overdrive or distortion on it's not an issue - but clean (which I play a lot) it just sounds bad.

But maybe that is my only alternative.

I know when I noticed the G String Warble on strats, I played every one in a store I worked in - and it was present on every single one of them. And then I couldn't unhear it (and it's probably on all classic recordings but I just can't get it out of my head).

Now that I've heard this, I can't unhear it.

:-(

Jussi
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Re: Inharmonicity of Guitar Strings

Post by Jussi » Mon Sep 25, 2017 2:25 pm

Great post Alan, a very intuitive explanation!

The following caught my eye:
Alan Carruth wrote:
Fri Sep 22, 2017 8:47 pm
On a wound string the stiffness that counts is that of the core; in theory, the windings don't contribute to stiffness.
Is this a result of the windings being able to 'roll' over each other in some sense, such that the material doesn't need to compress? Thanks for the explanation about the longitudinal wave as well. I think I've heard this called a 'phantom partial' before, where the two nearby peaks of frequency occur as you describe.
stevel wrote:
Mon Sep 25, 2017 12:24 am

So which is the more favorable ratio?
Hi Steve, according to the theory I wrote about, inharmonicity will decrease more rapidly with reducing radius than increasing tension (B varies with radius ^ 4, but tension ^-1) so the greater gain is made by reducing the string gauge than increasing tension (in this simplified theory, in practice many things may change this conclusion, like perhaps wider tolerances on the manufacture of thinner strings etc.etc.)
stevel wrote:
Mon Sep 25, 2017 12:24 am
Our Piano Tuner has a piano tuner that measures overtones - it actually allows him to store presets for various pianos - so each and every piano is different - this allows him to do precise stretch tuning for each instrument - he recalls the memory and tunes based on that (making adjustments of course).

I imagine there are many factors...
Yes I suppose no two pianos are created equal, the design and construction of each will change the effect. I'd be interested to find out how a piano tuner chooses what compromise to make when calibrating the 'stretch', I suspect there are competing schools of though on how to compensate for inharmonicity.
stevel wrote:
Mon Sep 25, 2017 12:24 am

Yes, I had heard this. I believe it's possible this may have contributed at least in part for the strings becoming the "core" of the orchestra - they played "in tune with themselves" which makes it easier for all of the members to tune to each other, and since they have not frets, can further refine to other temperaments as well.
Maybe! The thought occurred to me that this may be why they sound so 'natural' or 'lyrical' or voice like. I suspect there is a similar 'forcing' of harmonic content involved in the human voice which is why people often make such comparisons between voice and strings or, say saxophone. I'm just guessing though, and I don't know how I'd fit bagpipes and didgeridoos into that theory! :mrgreen:
stevel wrote:
Mon Sep 25, 2017 12:24 am

I'm also saddled (pun intended) with the issue of string to string balance and breakage - The B at the current tension is "floppy" - easy to bend a step and a half - but the high E is tough to bend that far at all. So a 10 or 9 would improve that, but, I'd be more likely to break it (which is why I went to 11s to begin with). That said, I once put a 19 wound G on, and broke it almost immediately - I think becuase it was SO much tension.

Also, the B as is is looser - under less tension because of its size (14) and doesn't warble, so I wonder if the High E being thinner would benefit.

But then I'll break it.............
Yes, these practical considerations are more important. That's why I suggested seeking every possible cause that isn't the string, combinations of setup etc. because ideally you want to be able to chose whatever type of string you prefer to play without having to consider this unusual issue. I think just finding that one perfect string that doesn't have the annoying sound isn't really the best solution because it might not be your favourite string to actually play with! Makes for an interesting conversation though!

Thanks
Jussi

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Re: Inharmonicity of Guitar Strings

Post by Alan Carruth » Mon Sep 25, 2017 5:45 pm

String length, tension, diameter and inharmonicity. That seems more complicated than it is; you just need to isolate variables.

Any two plain strings of a given material and length should break at the same pitch. In practice, thinner ones will go a little bit higher, but not much. This can be expressed as 'percentage of Tension'; %T: a plain steel .009"and a plain steel .014" will be at the same %T when tuned to high E on your guitar. The larger string will have more than twice the tension, since it has more than twice the mass, which is why the pitch comes out the same. However, the thicker string will be almost four times as stiff, and will be more inharmonic.

The bending stiffness of the string is the same, no matter how much tension there is on it. The lower tension on a given string the larger the ratio between bending stiffness and tension, and the greater the inharmonicity.

Windings (in theory) don't add to stiffness because they are put on the string under tension, and probably less tension than the string will carry in use. Even if the windings touch when they're put on, they should not when it's on the instrument. This doesn't hold for flat ribbon windings, which may be overlapped, or for strings with multiple layers of winding, since alternate layers cross each other. One of the problems with small pianos is that they have to use several layers of winding on the lowest strings, and these DO add a lot of stiffness.

The easiest way to rule out the L-wave as the cause of the problem is to simple change the tuning of the string a little, as I said, and see if it goes away. The problem comes in when the L-wave is an exact multiple of the string's fundamental; if it's not right on you won't have the problem. The L-wave pitch is pretty much fixed for a given string and instrument, but you can vary the fundamental easily. Try it.

One clue that the L-wave is the issue is that the problem shows up on a given string at every fret. 'Wolf' notes caused by resonances within the instrument show up at particular pitches and not others; re-tuning the string moves the issue to another fret. Fret problems show up at partcular locations along the fretboard; re-tuning the string makes the problem happen at a different pitch on the same fret. Issues with open strings that go away when they're fretted might have to do with the nut, or back strings buzzing on the frets. A miss cut saddle can cause issues on every note on a string, but a good setup should cure that. L-wave issues are not common, but they happen. As Sherlock Holmes said; once you have eliminated all the other possibilities, whatever remains, however unlikely, must be the truth.

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Re: Inharmonicity of Guitar Strings

Post by guitarrista » Mon Sep 25, 2017 6:10 pm

Alan Carruth wrote:
Mon Sep 25, 2017 5:45 pm
The lower tension on a given string the larger the ratio between bending stiffness and tension, and the greater the inharmonicity.
Are you sure this part is correct? It seems to say that the thinner string of the two in your example will be more inharmonic - which is the opposite of what one would expect give that thicker strings are stiffer as you say just in the paragraph before that. Or I am possibly not reading this right - for example of you mean instead the very same string, but lowering the tension and thus the pitch?
Konstantin
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Re: Inharmonicity of Guitar Strings

Post by Alan Carruth » Tue Sep 26, 2017 6:34 pm

I wrote:
"the lower the tension ON A GIVEN STRING..." That's the same diameter, material and so on, so, yes, lower the tension and pitch on the same string and the inharmonicity rises. Just trying to isolate variables, as I said.

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Re: Inharmonicity of Guitar Strings

Post by Joseph » Wed Sep 27, 2017 5:36 pm

On electric guitars this problem is almost always due to the saddle wearing in a groove from the string itself. Id recommend deburring
the saddle first with nut files the same size as your string and then polishing this out to 2000 wet and dry. If you dont have access to a good tech simply replace the saddle.
Joseph "Soxy" Price
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Specialising in Advanced Playability and Accurate Intonation

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Re: Inharmonicity of Guitar Strings

Post by guitarrista » Wed Sep 27, 2017 5:49 pm

Alan Carruth wrote:
Tue Sep 26, 2017 6:34 pm
I wrote:
"the lower the tension ON A GIVEN STRING..." That's the same diameter, material and so on, so, yes, lower the tension and pitch on the same string and the inharmonicity rises. Just trying to isolate variables, as I said.
OK, thanks, got it. I usually don't think about changing the pitch as we are sort-of stuck with the standard pitches/tuning for the guitar.
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