The "clothesline effect"
A stretched clothesline will sag more if you hang
a weight on the middle of the line, than if you hang it near the end.
Near the ends the line must be stretched more in order to move the same
distance. In analogy with the clothesline a string behaves in the same way. We can express the "clothesline effect" like this: The force needed to move a tight string a certain distance, perpendicular to the string, decreases as the applied force moves closer to the center of the string, and increases as the applied force moves towards either end of the string. Since the string must stretch more when it's fretted near the nut and high up on the fretboard, the tension will increase more near the nut and the upper end of the fretboard than if it's fretted at the middle of the fretboard. The "clothesline effect" tends to lower the pitch at the center of the fretboard. It will hardly be noticeable to the ear, because the faults are small and they increase gradually, but with an accurate tuner you can see the the effect. Preferably we would depress the strings a little deeper towards the middle of the fretboard. That's what we do with the right amount of release. |