String type & gauge question for Pre 73 bass owners

[DavyR]

Specifically, string tension can be calculated by the following formula:
T = (UW x (2 x L x F)^2) / 386.4
Where:
T is tension in pounds
UW is the Unit Weight of the string in pounds per inch (this takes into account the metallurgy, diameter, construction, etc.)
L is the scale length - the vibrating length of the string in inches
F is the frequency or pitch that the string is tuned to in Hertz
^2 means "squared"

Why doesn't the length from the ball-end to the tuning post a factor for tension since that is where the tension is created?
Thanks!

[cjj]

Specifically, string tension can be calculated by the following formula:
T = (UW x (2 x L x F)^2) / 386.4
Where:
T is tension in pounds
UW is the Unit Weight of the string in pounds per inch (this takes into account the metallurgy, diameter, construction, etc.)
L is the scale length - the vibrating length of the string in inches
F is the frequency or pitch that the string is tuned to in Hertz
^2 means "squared"

Why doesn't the length from the ball-end to the tuning post a factor for tension since that is where the tension is created?
Thanks!

Because it's irrelevant. The string tension is going to be the same over the whole length of the string, from the ball end, to the tuning post. The scale length and frequency are easy to measure accurately, the rest of the length can vary quite a bit without changing anything...