# string break angle-disscussion



## Canman (Oct 21, 2007)

On another thread the topic of headstock and bridge string break angles arose and got me 2 thinkin bout it

-thought Id toss it out 2 c if any 1 was intersested

-I suppose the nut and bridge break angles would absorb some of the strain at the ends but doest the string still need to have the same tension 2 get up 2 pitch? 

I dont know- I know a medeval lute has a almost 90degree angle and is quite loose.

The angle of the string across the bridge does effect the top of an acoustic guitars downward force, but in an electric does it have any effect?

And what about headstiock angles on electric guitars or guitars in general for that matter-does a strat have more tension than a les paul because of the head angle?

or Will a string always have the same tension at the same pitch? Or is it changed with the break angle and if so by how much?


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## Hamm Guitars (Jan 12, 2007)

I've actually done testing on this. The effective length of the string is from witness point to witness point (nut to bridge saddle). 

With all things equal the length of the string beyond the witness points is not a factor. However, the tension (downforce) of the string at the witness point effects the playing tension of the strings and this is determined in part by the break angle.

Increasing the pitch of the headstock increases the effective tension on the strings when tuned to pitch, as does lowering the tail piece on a TOM style bridge. Decreasing these angles reduces string tension.

It should be noted that a guitar with less tension requires you to stretch the strings further when bending than a guitar with more tension does to achieve the same pitch variance.

Maybe a lute would be really loose without the right angled headstock, or there may be an angle above 45 degrees where the tension decreases with an increase in angle - I didn't test anything more than 45 degrees.


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## Greenman (Feb 18, 2007)

Hamm Guitars said:


> However, the tension (downforce) of the string at the witness point effects the playing tension of the strings and this is determined in part by the break angle.
> 
> Increasing the pitch of the headstock increases the effective tension on the strings when tuned to pitch, as does lowering the tail piece on a TOM style bridge. Decreasing these angles reduces string tension.


Something doesn't sit right with that statement. I'm looking for an old thread that states otherwise.
Confused.


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## Canman (Oct 21, 2007)

Hamm Guitars said:


> I've actually done testing on this. The effective length of the string is from witness point to witness point (nut to bridge saddle).
> 
> ...tuned to pitch, as does lowering the tail piece on a TOM style bridge. Decreasing these angles reduces string tension.
> 
> ...



mmmm?
...Well I can see that decreasing the angle would indeed change the pitch but then you would have to adjust the tuner, increasing the string tension to get it back up, and therefore the strings tension is back to where it was.


I do however agree that the length beyond the nut and bridge would have some sympathetic effect on the tone.
I also realize that a shorter string length makes for less tension with the same gauge strings 
eg a Strat more than a prs and those 2 more than a gibson.

How ever even though the actual tension is less we lose some of the "bending" ease or mechanical advantage due to the decrease in length.

In other words we bend less for the same pitch...but there is less tension so...it equalizes out in the end...?

I would have to assume that all things being equal that there is no dicernable difference other than the miniscule distance difference one must pull the string to get the same variation of pitch.

I cannot see how the direction of the string beyond the nut or the bridge makes any difference in the string tension. 
But I really dont know anything about physics.


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## Hamm Guitars (Jan 12, 2007)

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

The tension I was refering to is the resistance to bending, in the article above the author calls it compliance. Increasing the break angle increases the friction at the witness points so it negates the effect of distributing the load over a larger string.

I didn't read the whole article above but I found that firm witness points - like a locking nut - cause the same increase in tension when bending as they shorten the 'stretchable' portion of the string. I've allways hated bending on the first couple of frets with a locking nut. 

My findings were:

shorter stretch length = tighter bend = less travel for a half step bend
longer stretch length = looser bends = more travel for a half step bend

Both require about the same amount of effort, but I like to bend further with less tension. This is similar to the difference between bending different guage strings (ie 10's as opposed to 11's)

I also find that the increase in tension is more pronounced the closer you are toward either friction point - so stretching fells easier in the middle of the scale.

Anyone with a TOM style bridge and seperate tailpiece can try this for themselves. Tune, bend at the 12th fret and see how far you have to bend the string to get a half step. Increase the break angle (drop the tailpiece) and test again. There is a region where you will find a difference, where the sadle friction is reduced enough that if you pick between the brige and tailpiece and bend a fretted note the 'harp note' will change. If you cant bend and change the 'harp note' you have too much sadle friction and your not getting a longer 'stretchable string' - and likely tuning stability problems (unless you have low friction sadles).


edit - yikes ! the tuning stabilty problem noted above was intended to be for low friction at the bridge with standard sadles. Too little downforce allowing the strings to bind.


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## Greenman (Feb 18, 2007)

Hamm Guitars said:


> http://liutaiomottola.com/myth/perception.htm
> 
> The tension I was refering to is the resistance to bending, in the article above the author calls it compliance. Increasing the break angle increases the friction at the witness points so it negates the effect of distributing the load over a larger string.
> 
> ...


Spent the last 10 minutes on that site. 
Thanks for the good link.


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## Hamm Guitars (Jan 12, 2007)

Sorry it was late when I wrote my last post and I don't think I was getting my root point accross.

Consider the following.

A double locking system with a blocked trem system has no 'extra' string length to draw on. When you bend the string length does not change. If you play the 'harp' on the headstock you cannot change its pitch by bending or stretching the strings in the fretted area. There are two speaking areas in this case and they are isolated from one another by the locking nut. This is the most extream case.

Now take the same guitar and put a tom bridge on it. It now has three speaking areas, the harp on the headstock, the normal fretted are that we play in and the harp at the bridge. When you bend the strings and you have enough nut friction that the string doesn't move at the nut or the bridge, you have the greatest tuning stability, you can't change either 'harp' note and the strings are at their tightest - the same as if you had a locking nut.

Now if you replace the nut on the guitar with something that glides - a roller nut, or a tremnut, or a lubricated nut the string dynamics change when you bend. I think I might have given the wrong impression of what was happening in my previous post - what I think is happening is that when you stretch the string you are pulling string accross the nut - the harp note increases because its tension increased. The fretted note string now has more 'slack', so it is longer as more string has been pulled past the witness point. As you bend, the string gets longer - not because the string is stretching but because you are pulling 'reserve' from accross the nut - this is why you need more travel in the bend to achieve the same pitch varience as you would with firm witness points. The string length change is slight, but even small changes in the sting length effect the pitch of the string.

The same thing can happen at the bridge end.

What is important is that the string length returns to normal when the bend is released, which is why low friction saddles and nuts are important. Those that like the feel of 'tight' strings would have no use for low friction nuts and saddles, but if you like that loose, elastic slinky feel and you want your guitar to stay in tune then they make sense. 

Some will argue that the tone and intonation of the instrument is better with firmer witness points, and they are probably right - but I personally like the feel of a guitar that has a little 'give' to it.

So - the pitch of the headstock or the pitch between the saddle and the anchor point effects how 'slinky' your bends feel as more friction does not allow more string to be pulled past the witness points. 

At least this is the result of my research.


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## Canman (Oct 21, 2007)

*ooohhhh...I see it now.*

Well I can see it-yes it makes perfect sense
anyways thanks for the informative link.


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