Compensating for nutcases

[Matt Bach]

So I have read the recommendations in another thread about compensated nuts and I would really appreciate if you could share some articles on this approach; I'd like to chew on this further. I'm yet to read anything that makes perfect sense to me.

It seems to me that making nuts this way is kinda locking the end user to a prescribed tuning and string gauge forever (either that or have it physically adjusted at each change)? The true temperament fret system looks cool (kinda) but they certainly lock the player into certain strings and tunings; so too bad if you want to try a wound G or an open tuning. Or is it a case of "some" compensation simply being superior to none? Or is the intention to never have the instrument deviate from standard tuning with standard strings, and if so, how do your customers feel about that?

Some of you guys say that once you hear the difference you will never go back. I will always admit my ear could be better but as I only really intonate open to 12th and then call it done, maybe I don't know what I'm missing. Should I be concentrating more on hearing/intonating other (probably more often played) intervals?

[Craig]

Matt , I've not gone to the trouble of compensating the nut to the degree of a Buzz Feiten system ,or that described in the Gore/Gillet book. ( Thus far . ) I've merely shortened up the end of the fingerboard ( a bit more so on the bass side )bringing the nut a little closer to the first fret. Technically not perfect , but makes a noticeable difference when playing within the first few frets.
With different string guages and considering not all guitarists fret with same amount of pressure , I guess there's no absolute way of ensuring perfect pitch on a guitar . Some say that a good guitarist will bring the string into tune themselves by varying the fretting pressure ( subconsciously)

[seeaxe]

I freely admit to not studying this at all and have not read Trevors no doubt excellent book, so I guess I am leaving myself open to being told I am asking a dumb question, but before I do spend a lot of time trying to understand nut compensation....

What happens on a nut compensated guitar when you play anything other than an open string? Isn't the compensation at the saddle then the only thing making any difference?

Cheers
Richard (self-confessed zero fret devotee!!)

[woodrat]

Hi Richard, I have not gone and done the full blown nut compensation from the G and G book but I did on my last two Journeyman guitars lop 1.5mm from the end of the fingerboard. This is the same as what Craig mentioned in his last post and the quick and dirty method that Trevor talks about in the book. It basically applies an average amount of compensation to each string at the nut and certainly does improve things as I felt they were sweeter in the first position...

John

[Trevor Gore]

I don't suppose anyone else is going to answer this....

It seems to me that making nuts this way is kinda locking the end user to a prescribed tuning and string gauge forever...

Well, standard compensation "locks" you in just as much, but to a wrong solution to the intonation problem. There is no combination of strings, relief and action that can be optimised with standard compensation. Standard compensation is just an approximate intonation solution that, if set up really well, is somewhat better than no intonation correction at all.

...Or is the intention to never have the instrument deviate from standard tuning with standard strings...

Nut and saddle compensation (if you know how to do it) can be set up to minimise intonation errors around any string set and set-up that the player chooses, but it is only optimal for that set-up. If you change string gauges or set-up significantly, you will probably still be better off than with standard compensation, but your intonation will be far from optimised. However, most serious players like to keep their instruments to a closely toleranced set-up, and adjust them so that that is the case. Occasional episodes in, say, drop D tuning are not a problem, but if you play permanently in DADGAD you might want your guitar intonation optimised around that tuning.

...maybe I don't know what I'm missing...

You don't know what you're missing until you hear a well intonated guitar (usually having nut compensation) side by side with a standard guitar. Even then, the difference doesn't bother many people, so you may not be missing anything at all. But, to the disadvantaged few who hear the difference (disadvantaged, because with standard compensation everything sounds out of tune!) there is no going back.

Should I be concentrating more on hearing/intonating other (probably more often played) intervals?

If the out-of-tuness of standard compensation doesn't bother you now, let it be. You'll be doing yourself a favour!

What happens on a nut compensated guitar when you play anything other than an open string? Isn't the compensation at the saddle then the only thing making any difference?

The nut to first fret distance is typically something like 35mm and that is equivalent to a semitone pitch change, (100 cents pitch change). If you move the nut toward the first fret by, say, 1.0mm, you'll get ~3 cents pitch rise (100/35). If you then drop tune the open string 3 cents back to concert pitch the note on every other fret is 3 cents flat. So the nut compensation effects all fretted notes by a constant amount. If you move the saddle say 1.0mm, the open string shifts 3 cents in tuning, but the string fretted at the 12th fret will shift twice that amount i.e. 6 cents from however sharp, flat or accurate it played before. So every fret will have a different pitch change for a 1.0mm shift in the saddle position. The trick (and there is a LOT of maths to this) is to balance those two different effects of shifting nut and saddle positions so that the intonation error on the strings and set-up you are using is minimised for all frets and all strings. No-one said this was easy...

However, the book looks at about 5 different ways to do "simple" nut intonation (as well as the mathematically intense ways) which work to a greater or lesser degree. The method that Craig mentioned is one of those. It works reasonably well, considering its simplicity.

[Clancy]

The nut to first fret distance is typically something like 35mm and that is equivalent to a semitone pitch change, (100 cents pitch change). If you move the nut toward the first fret by, say, 1.0mm, you'll get ~3 cents pitch rise (100/35). If you then drop tune the open string 3 cents back to concert pitch the note on every other fret is 3 cents flat. So the nut compensation effects all fretted notes by a constant amount. If you move the saddle say 1.0mm, the open string shifts 3 cents in tuning, but the string fretted at the 12th fret will shift twice that amount i.e. 6 cents from however sharp, flat or accurate it played before. So every fret will have a different pitch change for a 1.0mm shift in the saddle position. The trick (and there is a LOT of maths to this) is to balance those two different effects of shifting nut and saddle positions so that the intonation error on the strings and set-up you are using is minimised for all frets and all strings. No-one said this was easy...

I couldn't have said this better myself.
Seriously, I couldn't have said it!!

[kiwigeo]

I propose a much simpler system where the audience is compensated rather than the instrument. Everyone entering the concert hall will handed a slab of VB and a pair of industrial ear muffs. Audience members must don the earmuffs and skull the slab before taking their seats. With the audience fully cut and deaf a guitar with poor intonation is going to be the last thing they notice.

[woodrat]

Martin, I think Trevor missed that method in the book!

John

[Dominic]

I propose a much simpler system where the audience is compensated rather than the instrument. Everyone entering the concert hall will handed a slab of VB and a pair of industrial ear muffs. Audience members must don the earmuffs and skull the slab before taking their seats. With the audience fully cut and deaf a guitar with poor intonation is going to be the last thing they notice.

Nor that the 'guitarist' is actually playing a banjo.

[Bruce McC]

Good old Friday night.....................

"Nor that the 'guitarist' is actually playing a banjo"

where did the banjo come from and did it have a zero fret?

[seeaxe]

The nut to first fret distance is typically something like 35mm and that is equivalent to a semitone pitch change, (100 cents pitch change). If you move the nut toward the first fret by, say, 1.0mm, you'll get ~3 cents pitch rise (100/35). If you then drop tune the open string 3 cents back to concert pitch the note on every other fret is 3 cents flat. So the nut compensation effects all fretted notes by a constant amount. If you move the saddle say 1.0mm, the open string shifts 3 cents in tuning, but the string fretted at the 12th fret will shift twice that amount i.e. 6 cents from however sharp, flat or accurate it played before. So every fret will have a different pitch change for a 1.0mm shift in the saddle position. The trick (and there is a LOT of maths to this) is to balance those two different effects of shifting nut and saddle positions so that the intonation error on the strings and set-up you are using is minimised for all frets and all strings. No-one said this was easy...

Thanks Trevor for taking the time to explain this...I'll need to read this a few times more, I think.

Cheers

[weslewis]

I have done two 6 string guitars and one 12 string using Trevor's numbers, he was kind enough to send me the numbers for a 24.9 scale..
I leave the fretboard at the normal length and add a shim to the front of the nut then carefully measure and file...the results have been very good with just a few cents difference up the scale..I use a 5/32 inch saddle which give me room to compensate ..

[Matt Bach]

Thanks guys, it's getting clearer. Somewhat. Thanks Trev!

Honestly even doing a couple of guitars/basses a day for a few years I'm still trying to get MY fretting pressure totally consistent across the strings when intonating; as well as trying to match what the player does with his/her hands so as to achieve the best setup for them... I think I need a good long think before attempting to compensate a nut for Drop F or whatever is the cool kid tuning of the week.

I think Martin easily has the best solution so far.