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#16
11-24-2014, 02:25 PM
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One of our local luthiers, Chuck Baleno, has made this standard on his instruments... they play wonderfully in tune!
Warning, big pic... 
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________________________ Acoustic Music Works Guitars, Banjos, Mandolins & Good Company A top dealer for Collings, Huss & Dalton, Kevin Kopp, Baleno Instruments, Eastman, Pisgah Banjos, OME and ODE Banjos, Northfield Mandolins, and more! (412) 422-0710 www.acousticmusicworks.com Friend us on Facebook! Follow us on Twitter! Check out our YouTube channel! 
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#17
11-24-2014, 02:29 PM
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Hi ljg,
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By the way, I'm not for a second saying that slightly out is "bad"... it's not like I'm going to toss all of my other guitars out because I love them all. I'm just genuinely curious to know why compensated nuts haven't taken off more.
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Martin BC, Canada
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#18
11-24-2014, 02:34 PM
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The short answer as to why a compensated nut makes sense is that when you fret the string you stretch it at both ends, so both ends need to be compensated.
Suppose you set up a string on a rigid beam, to get any complications due to top and neck motion out of the way. We'll assume you've got the action set up well, and the nut and saddle, and all the frets are exactly in the proper places by calculation. Hook up a tuner to the P/U in the saddle, and what would you see? The notes fretted on the first fret would be slightly sharp. In pressing the string down to fret it you've stretched it, and the angle on the nut side is pretty large, so the tension changes more than you might think. All the higher notes would also be sharp. If you plot out the degree of sharpness, say in cents deviation from correct pitch, you'll get points that follow a line that rises: a few cents sharp at the first fret, and more and more sharp as you go up. That's because the strings get higher off the frets as you go up, so that have to be displaced more. Since the fretted notes are sharp you could correct their pitch by shifting the frets back toward the nut a bit. In fact, if you shift them all back by the same distance you'll flatten the pitches of all the notes by about the same amount in cents. But, of course, shifting all the frets back is the same thing as shifting the nut forward by the same amount. If the note on the first fret is 2 cents sharp, then shifting the nut forward by the right amount should flatten all the notes on that string by 2 cents. What you've done is to shift the whole line in the 'sharpness' graph downward. This still leaves the problem of the pitches going progressively sharp as you go up. That is dealt with by saddle compensation. Shifting the saddle back away from the nut adds proportionally more length to the strings as you go up. It changes the slope of the 'sharpness' line. If you do the usual thing, compensating the saddle but leaving the nut in the 'theoretical' position, you can get the note to be in tune at the 12th fret (or any other you choose). However, in lower positions they will still be sharp, and above the 12th (or whichever) fret they'll be flat. If you compensate the nut but not the saddle, the open string and the notes at the first fret (or, again, whichever fret you choose) will be right, but as you go up from the chosen fret they will go sharp. Compensating both the nut and the saddle can get you 'arbitrarily close' to perfect intonation, at least in theory. You drop the 'sharpness line' down to the point where the notes on the first fret are in tune with nut compensation, and then flatten out the slope of the line with saddle compensation so that all the notes are correct. A few caveats: This only works perfectly on rigid beams. On real acoustic guitars the bridge moves more at some frequencies than others, and when the bridge is moving the string motion doesn't end at the saddle, so the pitch can be off. Every guitar will likely have one or more notes that will be hard to get in tune, and the better the guitar the more likely that is to be the case. Every string is different. You have to set things up for the strings you use. If you use a lot of altered tunings you can't make them all perfect from one setup. A capo, in effect, pushes the strings down in another place, sharping them a bit more than they would be from just finger pressure on one fret. I've found that there's less need to re-tune with a capo when you have a compensated nut, but it doesn't eliminate it entirely depending on how fussy you are. 'Perfect' intonation only has some meaning in reference to a standard. In the case of guitar, the standard is 12-tone Equal Temperament. Since it's mathematically impossible to construct a scheme of temperament that gives perfect 'beatless' fifths all around, all temperaments are compromises that are more or less out of tune someplace in some keys. Equal temperament is out of tune in the same way in all keys, which makes it easy to modulate from one key to another. It also allows the use of straight frets, which we luthiers really appreciate. But there's no getting around the fact that ET is off in some intervals, and once you hear that it never goes away. Finally, Trevor Gore rightly pointed out in his chapter on the subject that once you've played a guitar that is in tune, it's hard to go back. One of my favorite guitars is out in the shop gathering dust because I haven't had the time to cut off the end of the fingerboard and make a new nut.
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#19
11-24-2014, 02:54 PM
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Many thanks for that Mr Carruth, very informative.
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Martin BC, Canada
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#20
11-24-2014, 07:07 PM
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Hear, Hear
I love it when someone who knows what they are talking about posts. And as for :
"Finally, Trevor Gore rightly pointed out in his chapter on the subject that once you've played a guitar that is in tune, it's hard to go back. One of my favorite guitars is out in the shop gathering dust because I haven't had the time to cut off the end of the fingerboard and make a new nut. " I totally agree.
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#21
11-24-2014, 09:59 PM
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Quote:
Pretty sure there is not unanimity on whether capos negate the effect of compensated nut even by builders… I find that as one plays further up the neck (where I do a lot of backing guitar) there are more 'obvious' out of tune notes. When playing up there, I just bend back notes into tune with the other notes in chord inversions. Actually I'm bending the in-tune note of the triad into better tune with a slightly sharpest one, and it sounds more in tune when all three are more closely aligned. I've heard people say they cannot find out of tune notes on their guitars, but I assure them that if they throw their guitar on a strobe tuner, and work their way fret by fret up the neck, they will discover interesting things about the intonation of their instrument. Buzz Feiten patented a system, which he claims has by carefully compensating the nut and saddle more perfect tuning is achieved. He didn't invent this, just patented it, as luthiers have been advancing the nut into the first fret a bit for decades as well as carefully compensating saddles, and Ervana has been selling compensated nuts for electric guitars for quite a while. I'm intrigued by intonation, have really good hearing and sensitivity toward in/out of tune-ness, and after playing guitars with all sorts of compensation systems and claims towards perfection, none of them have prompted me to have major work done on my guitars. I'm glad you found something that moves your playing to a new level. Why isn't it gaining more traction? I imagine the compensated nut is something like side-ports and fanned frets (multi-scale necks). They all serve some people well, but none have enough traction that all guitar makers are using them (or even offering them). And one can have a Feiten system installed on any acoustic guitar (which is a two pronged design compensation at both nut and saddle) for about $350 (the last time I heard a price quoted). Less money to convert an electric guitar. I have not tried either of these, but really would like to...  
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Baby #1.1 Baby #1.2 Baby #02 Baby #03 Baby #04 Baby #05 Larry's songs... …Just because you've argued someone into silence doesn't mean you have convinced them…
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#22
11-24-2014, 10:13 PM
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Chap,
Quote:
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Martin BC, Canada
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#23
11-24-2014, 11:53 PM
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Quote:
Jim
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Divots in my fingers Music in my head I wonder what would be If I chose car racing instead. Jim Schofield
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#24
11-25-2014, 12:59 AM
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Quote:
Mr. Gore's book provides a method for empirically deriving the amount of nut and saddle compensation that optimizes the intonation across the range of a particular guitar. He doesn't say, "Use these values", as Feiten does. If I recall correctly, Mr. Gore does not specifically detail the use of stretch tuning or 12th fret/12th fret harmonic offsets. Feiten's patents are available on-line. Do a search and you'll find them. If you wade throughout the math preamble, you'll eventually get to the actual values, offsets and stretch tuning method. Opinions vary on how to achieve the best intonation. Many players are satisfied with the poor intonation found on the average factory-made instrument. Thus, the subject is something of a moving target with a heavy component of subjectivity.
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#27
11-25-2014, 03:14 AM
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I'd never heard of such a thing before. Hmm. His may warrant further investigation.
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Martin D35 - 2006 Taylor 314ce - 2004 Takamine GS330S w/Fishman Rare Earth Fender Standard Stratocaster - 2000 Genz-Benz Shenandoah Jr
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#28
11-25-2014, 04:48 AM
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Quote:
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#29
11-25-2014, 07:08 AM
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Quote:
Also he gives a few methods of compensation. First empirical, then one titled "Intonation for a high performance guitar" pages of maths in that one but it looks very accurate. Then "compensation without most of the mathematics" which is pretty good. Then "compensation with even less mathematics" which he refers to as a "quick and dirty" method but it does seem that any of those methods he gives get you better intonation than standard 12th fret intonation. I hear your last statement and I suppose it is subjective when some people just hear better than others and some even though they hear something is a bit of out of tune they put up with it as part of guitar life and just work with it, still I want to eventually tackle the "high performance" cause the "quick and dirty" has me so impressed already, next step build more jigs or "test rigs and learn more maths. Handing a player a guitar that plays so in tune is a fine thing. Jim
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Divots in my fingers Music in my head I wonder what would be If I chose car racing instead. Jim Schofield
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#30
11-25-2014, 07:15 AM
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Quote:
Jim
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Divots in my fingers Music in my head I wonder what would be If I chose car racing instead. Jim Schofield
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