Simply stated, the difference between traditional (standard) intonation and better intonation is that traditional guitar intonation ignores the need for nut compensation. (Nut compensation is needed to compensate for the sharping from added tension when you fret a string.) Secondly, intonation error is further compounded by using the open strings (which are out of tune with the fretboard) as a reference for setting the bridge saddle.
The result of traditional intonation is that, when the open strings are in tune, the lower frets will play sharp, especially the low E and the unwound G (if applicable.) Only around the 12th fret will the guitar be in tune with the opens. The next step is for the player is to “tweak” (which really means detune) the opens until a few chords sound better (but then, of course, the guitar will be out of tune at the 12th fret).
In contrast, better Guitar intonation is done by first aligning the saddle(s) with the fretboard, by adjusting it to where two fretted notes (typically fret 2 and fret 14) are in good
intonation to each other, on each string.
This causes all the notes on the fretboard (with some limitations) to be in
good tune with each other. After this
is done, the nut is compensated to put the open strings in tune with the
fretted notes. This is done by
effectively adding the right amount of material to the leading edge of the nut
for each string. (There are a variety of ways to do this.)
Note: In both methods, it is necessary that proper attention has been applied to string choice, neck relief, action height at nut and saddle(s), etcetera, before any adjustment of the saddle or nut.
The most important advantage of traditional intonation is that it is quicker and cheaper than better intonation. Additionally, traditional intonation methods are well known; they are performed by a vast majority of luthiers. services and information are readily available in books and on the internet.On the other hand, knowledge and expertise in better intonation is usually hard to find. Helpful information is scarce, and is often confusing or misguided.** I am hopeful that this situation will improve with time
Unless you can do your own work, traditional intonation is, perhaps, the only choice for low-end guitars, cost being the main consideration. Also there are hobbyist players with non-critical ears that genuinely enjoy playing the guitar just as it is.
But, that still leaves a huge group of serious players, amateur and professional, who have spent a lot of time and money on guitars with wonderful craftsmanship and great acoustical quality! In my opinion, use of traditional intonation is the weak point of these guitars – hence the desire for better intonation.
Traditional intonation methods are based on simpler expectations, and should not be the only ready option! Intonation can be greatly improved without resorting to exotic effort and expense!
Learning the better principles of intonation is very worthwhile! It can be helpful in developing a clearer understanding of intonation procedures and results, because it is based on a more realistic, yet simple, model of guitar setup. Even if full re-intonation is not being contemplated, understanding the better model will enable one to ‘see’ useful changes that could be done economically.
For instance, if a player is a beginner or solely a rhythm player, playing on the lower frets, then replacing the saddle would most likely not be necessary, whereas compensating the nut could improve the intonation greatly. In the case of an electric guitar, the saddles are usually easy to adjust, so a person can do that at any time, at little or no cost.
Another example is that you can get a partial improvement by moving the whole nut slightly forward. This is not terribly hard to do, even with a hobby saw. In the case of a builder, it would be just a slight change in the design placement of the nut slot. After all, this, basically, is the main principle of the renowned Buzz Feiten System (along with patented tuning offsets which detune the opens slightly, in order to improve intonation of the fretted notes). Some guitars are built with the nut already moved forward (Owners and luthiers should be aware if this is the case on a particular guitar, before any work is done.)
**misguided: The best way that I can characterize the confusion I see in intonation improvement discussions is that people are so used to traditional intonation, they often fail to clearly see the two compromises that are taken in traditional intonation. (see the first paragraph of this page) or, more often, they are interested in nut compensation, but cannot understand how adjusting the nut would interact with saddle alignment. It seems they just can’t let go of making the open strings the focal point for all intonation measurements.