Scale Length and string tension - at what point can you feel it

Lester

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I have a 70's LP. "Plays like buttah" as the phrase goes. I acquired an Epi SL a while back. Did the frets, replaced bridge with an intonatable one, got the action almost as good as the LP. Plays nicely.

But, the Epi seems much harder to play as in "it's beating on my finger tips at 3x the rate". Like it has very high action. Or strings a notch or more thicker. But it doesn't,,, the action is almost the same (a wee bit higher) and they have identical 10's. (I can drop the Epi to 9's, but that's not the point).

I got to thinking and I measured the scale, where I found it was almost 1/4" longer to the bridge, give or take saddle position. I thought perhaps it was bridge positioning error, but when measuring to the center of the 12th fret, the Epi is 3/16" longer than the LP. So it's almost a 25" scale.

Is that enough length to account for a significant string tension increase? I'm thinking that stretching a steel string an extra 3/16" would require a significant amount of extra pull. But that's just a gut feeling. What are the numbers on this?
 

ARandall

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You won't get any difference from that miniscule alteration. And the epi might just use a decimal version of the imperial Gibson scale to look at the actual difference (assuming a mechanical measurement error wasn't made)
Its about setup. And not just the measurable aspects. Your 70's has a 14deg headstock angle, and the Epi will have a 17. That sort of like a permanent topwrap for the nut end. And then you have the different bridge type, maybe different frets......the list goes ever on.
But even then, I have got several guitars which have nominally identical specs and they feel different. Lets face it neck profile can make a guitar play massively differently too.

The problem lies in the fact these are not the same guitar. No instrument is ever the same - hence the difference.
 

Lester

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Yeah... I see what you're saying. Again, my gut feel is that "a piece of steel stretched between two points for the same distance (give or take my 3/16") acts the same ... but I guess this is highlighting the fact that the string past the nut and the bridge, as well as the angle, allows more or less movement and make a difference - despite arguments otherwise. I'd also forgotten than the Epi frets are taller than the LP's wide and low... and I'm probably pushing harder on the Epi strings than I need to.

Prob time to just buy the 9's and stop fretting about it.

Yeah, I posted that pun.

PS. The Epi has a pigtail wraparound and the LP is strung old-school (not wraparound). That would imply (according to lore) that the LP would be harder to bend on. Not the case.
 

mhr900ss

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My collection includes a bunch of Gibsons, an EBMM Majesty and a Strat. At present they all have the same 009-042 strings on them. The Majesty and Strat both have the same, longer scale lengths and trems, so the ball end of the strings takes a really sharp bend and disappears into the trem block; no extra string length for string stretch at the bridge. All have almost flat necks, really good frets and action set to just-not-buzzing. I also change strings regularly. I can very definitely feel the difference in the scale length with the same gauge strings but when swapping between them, I get used to it really quickly. I find it to be a much bigger difference when playing someone else's guitar with a higher action whatever the scale length. I can very definitely feel the difference going up to 10s on both scale lengths, particularly the longer one.

All of this a moot point; if the guitar feels hard to play as is then drop the string gauge!
 

01GT Eibach

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Uhhhh ... are you sure they are tuned the same? The EPI is not tuned to something higher?
 

CB91710

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Scale length absolutely makes a difference.
Can you feel the difference tuned sharp 1/2 step?
OK....
Take a Strat... 25.5" scale length.
Put a capo on the 1st fret.
You now have the same scale length as the Guild Brian May Red Special.
But it's tuned 1/2 step sharp.
So tune it to pitch...

Yep... 24" scale tuned to pitch has the same tension as a Strat tuned down 1/2 step.

The amount of string beyond the nut or saddle influences the feel... but not in the way you'd think.
You feel that it is easier to bend a longer string, but to increase the tension by the same number of pounds, which is needed to raise a pitch "x" number of steps, you have to bend the string farther across the neck.

Ultimately, a .010 string tuned to E4 on a 25.5" scale will have a tension of 17.8lbs
A .010 string tuned to E4 on a 24.75" scale will have a tension of 16.8lbs
A .009 string tuned to E4 on a 24.75" scale will have a tension of 14.4lbs
A .009 string tuned to E4 on a 24.75" scale will have a tension of 13.6lbs

So ya... String gauge has more of an effect than scale length, but physics says that scale length matters,

Personally, I used to run 10s on Gibsons and 9s on Fenders. Always felt the 9s were too "floppy" tuned to D or DADGAD.
I've now settled on 9-46 on everything. Maintains the beef on the bottom end of the 10s.
 

E.T.

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You can get numbers from:

T=4mLf^2

T being tension (Newtons), m, L, and f being the mass (kg), scale length (m) and frequency (Hz) of the string respectively. As tension scales linearly with scale length you have about 0.76% more tension on the Epiphone. What makes more difference is the length of string behind the tailpiece on the LP- when you bend or fret on that you're stretching a longer string overall (as it moves over the bridge), so the strain (extension per unit total length) on the string for a given bend is proportionally less on the LP on the stoptail epi even if the tension (calculated using the scale length) is the same- it takes a bit less force to bend (stretch) the string the same distance on the LP, though you get slightly less increase in pitch as a consequence.

Unless your '70s LP is a junior, in which case Math says it's mostly psychosomatic :cool2:
 

Michael Matyas

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Scale length is not the distance from the nut to the bridge saddles. To find your scale length measure down the exact center of the neck to the middle of the twelfth fret, then multiply by two. (I know you know this, but some players take it on faith that the bridge is properly located.). Lots of guitars have the bridge slightly out of position. Comparing the scale lengths of your two guitars might shed some light. Scale length is adjusted by setting your bridge saddles so you get the exact same note, only an octave higher, at the twelfth fret as at the open string. (I know this is basic stuff, but bear with me.)
Now let's talk about strings. Music wire is made by drawing wire through progressively smaller dies until the proper diameter or gauge is attained. Dies are very hard metal, but they do wear after miles and miles of wire have been pulled through them. Strings made from older dies will have a slightly greater diameter, and therefore more tension than strings made from brand new dies. That could account for the different feel, even if you are using the "exact same" brand and gauge on both guitars.
Now let's talk about metal fatigue on strings. Older strings that have been played a lot, especially if you do a lot of bending, will lose some of their elasticity and become harder to fret and to bend. They will carry the same tension to reach concert pitch as brand new strings, but since the metal has become harder and less elastic, they will be harder to fret and bend. So if the strings on one of your guitars are a lot newer, they will feel easier to play than the older ones.
So if the guitar with the tougher action has much older strings, put new ones on and it will be easier to play. If the harder to play guitar has a slightly longer scale length, you could try a set of nine-and-a-halfs. Several string makers offer a set that runs something like 9.5 to 44, which will probably feel close to the tens you have on the guitar that plays easier.
Pro secret: most big time guitarists change strings before every performance, and not just because they want to minimize string breakage. They also like the greater elasticity of new strings, which makes them easier to play on, and makes it easier to achieve consistent pitch control on bends.

I hope this helps.
 
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gball

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I have a 70's LP. "Plays like buttah" as the phrase goes.

Does your '70's Les Paul have the super-low-wide frets that many in the era did? One thing that I notice is when I switch from my '79 to one of my more recent Les Pauls with the current fret wire is that they feel pretty radically different. The '79 is super-fast and effortless and the newer ones definitely take a little more effort to play, at least when you first pick them up.
 

Lester

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Yeah, probably much of it.

Uhhhh ... are you sure they are tuned the same? The EPI is not tuned to something higher?

Nope, Identical pitch, same tuner.

...
Ultimately, a .010 string tuned to E4 on a 25.5" scale will have a tension of 17.8lbs
A .010 string tuned to E4 on a 24.75" scale will have a tension of 16.8lbs
A .009 string tuned to E4 on a 24.75" scale will have a tension of 14.4lbs
A .009 string tuned to E4 on a 24.75" scale will have a tension of 13.6lbs

Interesting. Tells me my minor difference, subject to remeasuring the scale properly per @Matyas 's post, is probably too little to notice.

You can get numbers from:

T=4mLf^2
....
Unless your '70s LP is a junior, in which case Math says it's mostly psychosomatic :cool2:

Interesting. Seem like it's time for a spreadsheet!

Scale length is not the distance from the nut to the bridge saddles. To find your scale length measure down the exact center of the neck to the middle of the twelfth fret, then multiply by two. ...

Now let's talk about strings. ...

Good direction, but the strings are both about the same age. I also measure them with a caliper because I'm always curious (Oh, and I have a caliper. So I use it. Like my laser thermometer when I was in AZ. I just had to know). They measured the same, give or take the accuracy of the caliper. I'll recheck to see if the Epi is by any chance on the large side of the accuracy.

Does your '70's Les Paul have the super-low-wide frets that many in the era did?

Yeah, as mentioned in my followup... I'm thinking that's a large part of it.
 
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Lester

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FWIW, I remeasured the scale lengths again.

LP: 12 9/32" center of 12th fret. Calculated scale x2 = 24 18/32 (24.563). Actual measure to center of (fixed) bridge at center = 24.72". Oddly, it intonates perfectly and the saddles aren't at the limits. They look "normally" distributed.

Epi: 12 3/8" center of 12th fret. Calculated scale x2 = 24.75. Actual measure to center of (adjustable Pigtail) bridge at center = 24 27/32 (24.85). This guitar is perfectly intonated but there is some significant variation in the saddles although nothing is at the extremes. I did move the bridge back a bit to get the saddles better distributed across it when intonated.

I used a ruler marked 32's for the measurement... so measurements are +/- 1/64"
 

ehb

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I put Gib BR 10s on my Lesters.
I put Gib BR 9s on my Fenders.

They are tuned standard.
They feel about the same.

Pondering food: Play primarily Skrats for a long time and play a Lester and you'll bend sharp. Converse is also true. You'll bend flat. Muscle memory messin' yo groove, mang....

Scale length, distance... Think it out.
 

jvin248

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.

+1:

9s on a Fender are like 10s on a LP
PRS guitars are built with a 25 inch scale and is a 'happy medium' Goldilocks kind of string tension.

Billy Gibbons plays 7s Fender / 8s on a LP after BBKing convinced him that 8s on his Gibson were awesome for bending notes and not on a thick-string-tone-chase asking "why are you working so hard?" with 12s/13s on his Fender Tele.

.
 

Oranjeaap

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Many people did the science, some even on a level 99% of us don't have the education and/or brain for to understand :rofl:
Luckily for us, any good scientific article has a conclusion section and that part is usually easier to understand than the result section which contains all the maths and graphs and results from experiments.

There is a bunch of things that impact how easy/hard it feels to play a guitar, some of them obvious, some of them less obvious, all of them backed up by proper physics.
Then there is some parts that are not realy 100% explainable by any physics law (like string length outside the nut and bridge).

Last but not least there is stuff that according to physics should have no effect at all and people still claim it has effect

Sooo, lets start with: what is it that feels more difficult on the epiphone? Fretting, bending, or both?
The answer to this can narrow things down by a lot already.
 

E.T.

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LP: 12 9/32" center of 12th fret. Calculated scale x2 = 24 18/32 (24.563).
Now we know where PRS gets it from!
Then there is some parts that are not realy 100% explainable by any physics law (like string length outside the nut and bridge).
It's definitely all explicable by the laws of physics- just not entirely by simplified ones. I calculated a balanced tension set using simple math, then realised on consulting the tension chart that wound strings have different ratios of core to wrapping thickness, which threw the calculation into a cocked hat and left me with a set almost as unbalanced as regular 10s.. Less non-compliance with the laws of physics, more subtleties not accounted for by simple models :cool2:

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Lester

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9s on a Fender are like 10s on a LP
PRS guitars are built with a 25 inch scale and is a 'happy medium' Goldilocks kind of string tension.

So.... 9.5's on a PRS?

Billy Gibbons plays 7s Fender / 8s on a LP after BBKing convinced him that 8s on his Gibson were awesome for bending notes and not on a thick-string-tone-chase asking "why are you working so hard?" with 12s/13s on his Fender Tele.

Billy did say that BB King said "why are you working so hard". But, according to what BB says, he plays 10's. (n one of his training videos he mentions he's playing 10's). Seems he might have originally been referring to Billy playing 13's vs. his (BB's) 10's. Billy apparently decided to take it further down to 8's.

... which threw the calculation into a cocked hat and left me with a set almost as unbalanced as regular 10s..

Curios: Have you tried any of the so-called "balanced" sets?Or are you just trying to blend up your own?
 

E.T.

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Curios: Have you tried any of the so-called "balanced" sets?Or are you just trying to blend up your own?
Had to formulate my own, as the ones available are designed for normal tunings.. one guitar has a 17 gauge set for double drop Ab sub-baritone tuning, and the other one is in a constant drop Db which needs a set based on a 10.5
 

CB91710

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Now we know where PRS gets it from!

It's definitely all explicable by the laws of physics- just not entirely by simplified ones. I calculated a balanced tension set using simple math, then realised on consulting the tension chart that wound strings have different ratios of core to wrapping thickness, which threw the calculation into a cocked hat and left me with a set almost as unbalanced as regular 10s.. Less non-compliance with the laws of physics, more subtleties not accounted for by simple models :cool2:
And all of the "balanced tension" sets I've seen go the wrong way, heavier gauge strings on the treble end and lighter on the bass side.
I prefer heavy bass.
 

CB91710

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Billy did say that BB King said "why are you working so hard". But, according to what BB says, he plays 10's. (n one of his training videos he mentions he's playing 10's). Seems he might have originally been referring to Billy playing 13's vs. his (BB's) 10's. Billy apparently decided to take it further down to 8's.
Ya, I have my doubts that the conversation took place... at least not as it was related.
It just happened that Billy told that story right around the same time that Dunlop released his line of strings.
And Billy is well-known to spin a tall tale or two and provide intentionally misleading information regarding his gear and setup.

He's an awesome musician and I'm sure a wonderful person... but he is also protective of what he may consider to be "proprietary" information.
 

kakerlak

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Ya, I have my doubts that the conversation took place... at least not as it was related.
It just happened that Billy told that story right around the same time that Dunlop released his line of strings.
And Billy is well-known to spin a tall tale or two and provide intentionally misleading information regarding his gear and setup.

He's an awesome musician and I'm sure a wonderful person... but he is also protective of what he may consider to be "proprietary" information.
I'd like to know when he went to 7s/8s, etc, because his playing, especially live, is sloppy as hell these days. And it's sloppy in the very way a set of silly thin, squirmy strings would tend to cause. Chords out of tune with themselves, inaccurate bends, etc.
 

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