Questions on improving intonation (tone)

[mirwa]

Originally Posted by redir

For the sake of argument just pretend that there is no such thing as a nut, that all guitars just have frets on up to zero then the strings go to the tuning posts. So all ya got is frets. To build a guitar like that you would level the fretboard, install the frets, then level and dress the frets. Then you would string it up and set the action at the saddle and the relief. The guitar would be set up perfect.

Now just remove that fret and install a nut in it's place. The slots of the nut are the exact same height as the fret you just removed. IOW the nut is really just another fret...

IDK how to explain it any better but that's all there is to it. The nut is just a fret, it doesn't matter when in the process of doing a set up you cut the nut slots, before or after setting the saddle height, before or after setting in the relief, what ever. IT don't matter. As long as that nut is the same as the frets you are good to go.

This

Steve

[bausin]

>> Then you would string it up and set the action at the saddle and the relief. The guitar would be set up perfect.

When you say "perfect", does that mean the action can't be lowered without causing buzzing? Otherwise, please define "perfect".

[LouieAtienza]

Originally Posted by bausin

>> Then you would string it up and set the action at the saddle and the relief. The guitar would be set up perfect.

When you say "perfect", does that mean the action can't be lowered without causing buzzing? Otherwise, please define "perfect".

I'm curious as well. It's only perfect if the neck takes on a perfect "relief" shape.

[redir]

"perfect' is a moving target. It depends on the customer. Most seem to want the action as low as possible. So in that case yes, you would not be able to lower the saddle any more without getting buzz. That version of 'perfect' would be that string height which is just above the buzz threshold.

Again, the nut is just a fret, it doesn't matter at which stage you set it up. I thought the very same thing for many many years before someone else explained it to me and the light bulb went off. It plain and simply does not matter at what point you cut the nut in a setup procedure... It's just another fret

[bausin]

>> ... 'perfect' would be that string height which is just above the buzz threshold.

When you add relief, what happens to the action at the first fret?

[charles Tauber]

Originally Posted by bausin

When you add relief, what happens to the action at the first fret?

That is what the responses so far have not addressed and what your experience is telling you.

If you start with, say, .01" of relief, set the nut slot height to "the fret plane", then straighten the neck to zero relief, the strings will buzz on the first fret: the geometry has changed. That should be self-evident.

Not convinced? Take your "perfect setup" then adjust the truss rod until there is some back bow. Then tell us that the amount of relief has no influence on string height at the first fret. (One method for eliminating "back-buzz" is to slightly increase the amount of relief, effectively raising, slightly, the string height above the frets from the nut end of the fingerboard.)

The reason that I posted a link to Kimsey's site was because he has actual measurements of how much string height at the first fret changes in relation to relief. It isn't difficult to take those measurements, but few seem to have actually, quantitatively, done so.

[mirwa]

Originally Posted by bausin

>> ... 'perfect' would be that string height which is just above the buzz threshold.

When you add relief, what happens to the action at the first fret?

Clearly if you add relief the string height is going to go up over all frets not just the first, but it is still completley irrelevant when cutting a nut to the correct height.

I recommend you go do a local setup course, bound to be one on offer somewhere, trying to describe and explain something vee an internet forum is not working for you as we are now 6 days later and still going around and around the mulberry bush as they say.

Steve

[mirwa]

Originally Posted by charles Tauber

That is what the responses so far have not addressed and what your experience is telling you.

If you start with, say, .01" of relief, set the nut slot height to "the fret plane", then straighten the neck to zero relief, the strings will buzz on the first fret: the geometry has changed. That should be self-evident.

Not convinced? Take your "perfect setup" then adjust the truss rod until there is some back bow. Then tell us that the amount of relief has no influence on string height at the first fret. (One method for eliminating "back-buzz" is to slightly increase the amount of relief, effectively raising, slightly, the string height above the frets from the nut end of the fingerboard.)

The reason that I posted a link to Kimsey's site was because he has actual measurements of how much string height at the first fret changes in relation to relief. It isn't difficult to take those measurements, but few seem to have actually, quantitatively, done so.

Your confusing even me here charles, are you inferring that you cut the nut height subject to the string clearance and not the fret height?


Steve

[redir]

Originally Posted by bausin

>> ... 'perfect' would be that string height which is just above the buzz threshold.

When you add relief, what happens to the action at the first fret?

The action at the first fret rises... Next question?

[redir]

Originally Posted by mirwa

Your confusing even me here charles, are you inferring that you cut the nut height subject to the string clearance and not the fret height?


Steve

He did specify the 'fret plane' rather then the 'height of the frets'. I think that is the difference. But I will let CT speak for hiself.

[LouieAtienza]

Originally Posted by redir

"perfect' is a moving target. It depends on the customer. Most seem to want the action as low as possible. So in that case yes, you would not be able to lower the saddle any more without getting buzz. That version of 'perfect' would be that string height which is just above the buzz threshold.

Again, the nut is just a fret, it doesn't matter at which stage you set it up. I thought the very same thing for many many years before someone else explained it to me and the light bulb went off. It plain and simply does not matter at what point you cut the nut in a setup procedure... It's just another fret

That only works however if you start out with the fret tops on the same plane, relying on the natural "bow" of the neck under tension to effect the correct relief. This does not work however if the relief is shaped into the fretboard surface, with the frets following said surface. You couldn't datum off the first two frets because that would give a fret slot height that's a tad lower than ideal. You couldn't use the first three frets because the second fret would be a tad lower than the first and third, in the eye of a 3-fret straightedge.

To get the lowest action possible, or the "rock and roll" fret job, requires a shape as I described above. This is because the strings do no vibrate on a perfect parabolic arc as many would think. And this is not a new concept - people have been shaping fret tops (and fret boards) this way for years. A PLEK machine can do this by analyzing an unfretted board before and after tension, then shape the fretboard thusly, before the frets are installed.

[bausin]

>> I recommend you go do a local setup course ...

Let's see how this plays out before you send me back for remedial training.

[charles Tauber]

Originally Posted by mirwa

Your confusing even me here charles, are you inferring that you cut the nut height subject to the string clearance and not the fret height?

No. However, the common test of fretting on the wrong side of fret 2 to observe the clearance between the bottom of a string and the top of the first fret does exactly that.

This portion of the discussion started with MC5C stating that he cuts nut slots to be perfect then, six months later, reduces the relief in the neck and gets buzzing of the open strings at the first fret. He reported that if he reverts to the original relief, the buzzing ceases. He stated he didn't understand why.

The only point I'm trying to make is in answer to his statement. That is, that changing the geometry/curvature of the neck changes the "next fret clearance". Specifically, reducing the amount of relief in the neck reduces the clearance of the open string above the first fret, exactly what MC5C experienced. I had thought that influence was obvious. Most of the discussion that followed his post either ignores that influence or denies it.

[mirwa]

Steve

[redir]

I am certainly not denying that changing the relief will also change the height of the string at the first fret. What I am saying, again, is that if you get buzz when flattening out the relief it's not because you didn't set the nut up last in the process of doing a set up, it's because it's too low!

Again, the nut is just another fret