Scale length and string tension

[Acousticado]

Assuming the same brand/gauge of strings are used on different guitars of the same scale length, will the tension be/feel the same? I think it should, but I swear that the string tension on the 6 string neck in particular (25.5") of my all-carbon fiber Emerald Chimaera 6/12 doubleneck feels slightly greater than the tension on my Taylor 814c of the exact same scale length. Are there factors other than scale length (e.g. stiffer neck material...wood vs. carbon fiber) that could actually result, or make it seem like greater tension under playing conditions? It's not a big deal at all...just curious.

[Darwin]

I would think the tension would be the same. I do notice a difference between 25.5 and 24.75 using the same brand of strings. The short scale seems to allow easier string bending. -- Darwin

[Doubleneck]

Interesting today I decided to do a marathon, restringing my main three guitars and play them side by side with the same strings: light gauge PB DiAdarrio. My doubleneck like yours is 25.5, my Rainsong Jumbo is the same 25.5. My wood McKnight is 25.25. I played them all afternoon side by side. I think there is no question that the same strings over the same scale length would produce the same tension. But though guitars are very close to the same tension feel, there is a different feel. I think the biggest factor will be setup. My Rainsong probably has the best setup. I sanded the saddle and tweaked the truss rod to about perfection. The Emerald is close but not as low as the Rainsong. It becomes a wash I think because the neck profile on the Emerald is a little easier for me. The McKnight is almost indistinguishable as to pressure but neck probably the best for my style.

The pure pressure question given the same scale length will come down to saddle height and relief. Feel mixes in neck profile.

Going to record all three tomorrow to really see more objectively the sound comparisons.

[Acousticado]

Steve, yep, I agree that setup is the varying factor hat could cause a different tension feel, even if slight.

[Doubleneck]

Originally Posted by Acousticado

Steve, yep, I agree that setup is the varying factor hat could cause a different tension feel, even if slight.

Since you have a truss rod in your Emerald you should be able to get close to your Taylor. I have a gauge I bought to exactly measure my string height at the 12th fret. I will sand my saddles down using that gauge as a reference. Some necks just can get lower than others. I set my relief first to just a little less than flat and then sand to usually under 6/64 at the 12th.

[AcouStickistNS]

I've always noticed that DAddario often prints what tension it takes to bring a certain string to pitch. Some string manufacturers do better than others with respect to keeping variability between the same sets when you replace them. Not sure if it affects tension, but a pro bass player long ago had pointed out to me that how strings are packaged can also affect them. Air over time can affect an unsealed set's tone. That was part of what started cryogenic strings, don't recall if they made those for acoustics.

Forgot the brand, but way back when I had started playing bass guitar, one MFG had this annoying issue of not winding the ball end cleanly and the excess would bind in the hole of the bridge. Set to set the string either would anchor properly or on the excess.

Typically the difference would be in the guitar setups, but there's that small chance you get an oddball set that varies. If you get one, it's best noticed when changing sets in the same guitar.

[MC5C]

Tension and feel are two different things. Tension is determined by the physics of the string and the scale length, and that's it. There might be a tiny difference in true string length vs scale length from instrument to instrument, but the tension is a physical property of the string, the length and the pitch.

Feel is a lot more subjective. Action height plays a big role, as does fret size, neck profile, fingerboard width. One thing that is less thought of is the overall length of the string from tuner to tailpiece. When you press a string down to the fret, you feel both the initial tension and the increase in tension needed to stretch the string. A string with a very short installed length will feel stiffer to press down than the identical string with a long total length, simply because the stretching of the string to get it down to the fret is over the total length of the whole string. Various archtop tailpieces have attempted to profit from this, the Epiphone Frequensator being one such device.

[sirwhale]

Originally Posted by MC5C

Feel is a lot more subjective. Action height plays a big role, as does fret size, neck profile, fingerboard width. One thing that is less thought of is the overall length of the string from tuner to tailpiece. When you press a string down to the fret, you feel both the initial tension and the increase in tension needed to stretch the string. A string with a very short installed length will feel stiffer to press down than the identical string with a long total length, simply because the stretching of the string to get it down to the fret is over the total length of the whole string. Various archtop tailpieces have attempted to profit from this, the Epiphone Frequensator being one such device.

This is an important point, and I think, to a similar effect, how easily the strings can move through the nut slots and over the saddle.

I believe that a tight nut slot plus a really steep break angle over the saddle, will make for a "stiffer" feel.

[rick-slo]

Originally Posted by sirwhale

This is an important point, and I think, to a similar effect, how easily the strings can move through the nut slots and over the saddle.

I believe that a tight nut slot plus a really steep break angle over the saddle, will make for a "stiffer" feel.

In normal fretting the string will not budge at the nut, let alone at the bridge.

Rick;

It is my belief that strings move from the tuners to the tie. It will be interesting to hear what others have to say.

[sirwhale]

Another thing that changes the feel is the height of the frets. You have to press harder for lower frets.

[Silly Moustache]

1. Same strings, same tuning, same scale, same action = SAME.

2. Same strings, same tuning, same scale, different action = NOT THE SAME

3. Same strings, same tuning, shorter scale, same action = less tension, easier to play, less power.

You get the picture.

Action is also an important aspect.

[turbotom1052]

Originally Posted by sirwhale

This is an important point, and I think, to a similar effect, how easily the strings can move through the nut slots and over the saddle.

I believe that a tight nut slot plus a really steep break angle over the saddle, will make for a "stiffer" feel.

This is the very reason you see so many people wrap the tailpiece of their Les Pauls. By going over the tailpiece instead of the normal through tailpiece the break angle is reduced, resulting in a more floppy string press.

[David Eastwood]

Originally Posted by turbotom1052

This is the very reason you see so many people wrap the tailpiece of their Les Pauls. By going over the tailpiece instead of the normal through tailpiece the break angle is reduced, resulting in a more floppy string press.

Over the tailpiece or through it, the tension in the string is exactly the same, so it can make no difference to how much effort in how hard the string is to press down. Tension is independent of break angle.

What *can* affect the way a string feels is the length between the nut and the tuner, and the bridge and the tailpiece. That’s because, when you fret or bend a string, you’re affecting the total length of the string from one anchor to the other - the tuner to the tailpiece, not the nut to the bridge. The longer that total length is between the anchors, the easier the string will be to fret and bend, as the small increase in tension resulting from either of those two actions is less pronounced, the longer the total length of the string under tension.

If you wrap the string over the tailpiece, rather that run it through it, it’s conceivable that the total length of string under tension could be about half the width of the tailpiece longer, depending on where it is in contact with the tailpiece. Whether anyone could actually detect that tiny proportion of the overall string length is debatable - but guitar players claim all sorts of things all the time

(BTW, what’s this doing in the CF sub-forum?)

[jonfields45]

For the same pitch and string the relative tension goes with the square of the ratio of the scale lengths (if I did the algebra correctly...). For example, taking a RainSong and going from the 12-fret 24.9" scale to the 14-fret 25.4" scale would raise the tension (25.4/24.9)^2. Roughly 4% more tension for the same pitch, identical string.

https://www.hago.org.uk/faqs/formulae/