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Tonight I attended a free lecture/sales pitch by Robert Godin.
I was initially inclined to leave as he explained various rudiments
but stayed mainly because of his real enthusiasm, and I didnt have anything else to do but wait for the prize guitar raffle.
No joy there.
Two of the things he said interested me
1. A wide traditional type peg head will twist/trouble more during tuning than a snake head with a straighter string run."did you ever see a wide violin or cello peg head".... his words.

2. The effect of scale length on string tension is not just a factor of Nut to Saddle
but also of Tuning peg to saddle.
In other words if you increase the distance between the nut and the peg the tension increases


#1 seems entirely plausible to me
what about #2?

Sort of surprising that someone of his stature would have this common misunderstanding of string physics.

Maybe I didnt explain the second point too well

His contention was that if you take a strat
put on two identical e, strings
one where it normally would go, the other where the bottom E would go
Tune them identically
The top one would be under more tension than the bottom one on account of its greater length overall.

This was of interest to me as a classical builder where I think a little extra tension makes big difference
According to this theory one can increase string tension by
changing peghead layout and lengthening the peg to nut distance.

So this got me wondering does a tailpiece bridge increase LOA and string tension aswell
or is this nonsense?

Aha, the second point is about "compliance vs string tension". Hopefully The Padma is around to explain this one better than I could.

cheers

This is incorrect. The after-length of a string on the other side of the nut or saddle makes no difference to the tension.

A pretty thorough discussion about this can be found at:

http://liutaiomottola.com/myth/perception.htm

It talks about an experiment that Bob Benedetto conducted for an article in American Lutherie #68 and the conclusion he came to.

cheers

Hello, yes it makes a differnece in "stringtension" better "compliance or elasticity", feeling etc if you change the lenght between nut and tuners and / or tailpiece, bridgepinholes and bridgesaddle. For example there are some Gibsons and / or Epiphones around which have this strange tailpiece where you can adjust the length between tailpiece and bridge. Also there are tailpieces wich have a quite big difference in length between the tailpiece and the bridge regarding the 3 low and the 3 high strings. So also a guitar with 6 in line pegheads, like fenders etc, change there "tension-behavior" if they have a reverse headstock. I recommend literature from Eberhard Meinl, a german Proffessor who is examing stringed instruments on a professional science level for over 45 years now.

best regards, Alex

http://www.fiedler-guitars.de

It may change the feel of the string (the amount of force required to stretch the string), but it does not change the tension. Some folks do not understand the difference between these two and this may be the basis of people's misunderstanding.

Thanks that makes complete sense.
In defence of Mr Godin (who is very French Canadian) this may have been a question of semantics
and my comprehension rather than misinformation.

Benedetto's research showed pretty clearly that there was no difference in 'feel' when extra string length was added beyond the saddle or nut.
The mind is a powerful thing; it's hard for us to recognize that visible differences may not produce the tactile results we expect.



This is the opposite of the widely held idea about compliance: that the longer string length (beyond nut and saddle) makes the string easier to bend, i.e. feel like it is under less tension. The fact that different people looking at the same situation can predict opposite results from what they see should be a bit of a giveaway, I think.

Cheers
John

Easier to bend a certain distance...yes...
Easier to bend a certain interval...no...

To bend a string to a given note from another, you have to increase it's tension by a certain fixed amount. Increasing the tension between two points takes the same amount of force either way, but it's exerted over a greater distance if the string is more compliant. So it physically bends easier, but bending to a certain pitch takes just as much effort.

Less compliance means you need to bend the string less distance, so you can perform a larger bend pitch-wise with a smaller movement. More compliance means you need a larger movement, and are more likely to run out of space, but you might get a little more control over the bend since it's more 'spread out'.

The players likely wouldn't notice a difference even with a frictionless nut because they weren't paying attention to how far they physically moved the strings, just how hard they were pushing and how much the pitch changed.

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services