Finger bridge

[ironmike]

Anyone out the ever reverse the finger bridge pieces so that rhe low  e string is short and the high is in longer,everything in the opposite direction, I know it will increase the tension on the high end and lower the tension  towd th low e. But waht dynamic results has anyone found.

[TalismanRich]

I don't think it will make a significant difference in the tension or in "dynamics", but it will play havoc with the intonation.   The reason the bridge points end up where they are is because that is the point where the 12th fret harmonic is equal to the fretted note.

[RJLII]

I think he was referring to the tailpiece fingers where the strings anchor. 

[TalismanRich]

That makes more sense.   In my defense,  I've seen some people try some WEIRD things.

I still don't know that it will make a big difference in tension.   For  a given string diameter, and scale length, the tension should be the same to reach pitch.   I would think it might give a little easier bending since the elongation is spread over a slightly longer total string length but I don't know that it would be a significant percentage.

[bolero]

I recall reading *somewhere* about why & how they designed the finger tailpieces the way they do

I cannot remember where it was. But it must be out there on the internet somewhere.

Or god forbid, just ask AI ?

[ironmike]

I know for sure that the longer the string is from tuning peg to the anchor point,the higher the tension required to bring to pitch, so the lower string would be looser and the tension would get progrrssivle higher towards the high e string. This I know, but does anyone have it set up that way? The gibson citation is rigged that way. Just looking to hear from experience. Anyone?

[nuke]

I think only the length of the scale determines tension for any particular gauge/weight of string. So the distance between the nut and saddle a determinant, but the distance from saddle to stop bar is not part of the equation. 

There are a certain amount of harmonics present on the string outside of the scale length, and this can have an effect on sound. The string between tuner and nut, and between the saddle and tail piece are audible if plucked, and a certain amount of sympathetic vibration happens when the intentional note excites the string beyond the nut and saddles. 

I've occasionally stuffed the head stock of basses and a guitar or two to stop the weird ringing overtones that come that. It seems more apparent to me on bass, FWIW. 

I'd tend to think that the finger tailpiece was probably designed for appearance primarily. It sure looks nicer than a trapeze tail. 

 

 

[ironmike]

actually, the perfect distance from bridge to saddle id 1/6th the scale length, this is true for all violins, mandos. chellos archtops, rarely employed..the tension is alway determined by over all string length, as its entire length must be brought to tension and the longer it is the heavier it is and therefore more tension to suspend it at that tone.  this in known, what i am inquiring about is not theoretical, it is a practical question directed at the actual experience someone here may have or  had playing the finger bridge in a reverse  assembly,  such as i have seen in the gibson citation...and a howard roberts fusion. would love to try it next time i wear out a set of strings.

[nuke]

I don't think that's actually true. 

I went and looked in my old physics book and then confirmed a few other sources as well. 

The reference calculation is called Taylor's Formula:

F = m * f^2 * L^2

The length (L) only refers to the vibrating length of the string, between the inside edge of the saddle and the inside edge of the nut. What we guitar players call "scale length". 

These links discuss orchestral instruments, but the math is applicable to guitars as well. 

https://www.thomastik-infeld.com/en/stringtelligence/string-technology/do-changes-in-frequency-or-vibrating-string-length-affect-the-string-tension 

This one is also by TI but covers more of it in a single article:

https://www.thestrad.com/accessories/stringtelligence-by-thomastik-infeld-vibrating-string-length-and-string-tension/9132.article

 

I know this comes up a lot in electric guitars, and acoustic flat tops as well, with regard to the break-angle over the bridge. For instance, the practice of top-wrapping the strings over a Tune-O-Matic tailpiece versus using the holes. It is often said it reduces string tension and make them more "bendy" but tuning the same mass to the same pitch on the same scale, would necessarily mean the same string tension. 

The break angle does though, alter the down-force of the bridge against the soundboard or body of the instrument. 

Here's a calculator that will compute the force exerted on soundboard once the string tension is known:

https://www.liutaiomottola.com/formulae/downforce.htm