Classical Guitar action

[Steve N]

Over the years I've learned a great deal from Frets.com as far as the basics: string changing, checking neck relief and action. All this due to the fact that my daughter plays guitar and I've had to learn this stuff, along with learning to play myself. This is my problem: I just purchased a classical guitar for her - she's heading in this direction - and most of the info on Frets.com is geared towards steel strings. What should the neck relief be (measured at the 6th fret), what should the action be at the 12th? I know the action on these classicals is somewhat higher. Also, after a while I'll end up upgrading the nut and saddle to bone - anybody have any experience with using Ivory for this instead of bone on a classical?
Thanks in advance

[Brent Hutto]

Go to Kenny Hill's web site and under the "News" heading there is a link to a summary article about how he sets up guitars. Keep in mind that he builds classical guitars with a truss rod and likes to use that as a way of getting the action as low as possible, in fact lower than some players might prefer. From memory, he likes somewhere in the neighborhood of .110" on the treble side and .130" on the bass side at the 12th fret but he measures with the string fretted at the 1st. If you measure the usual way with an unfretted string your numbers will be .015" or so higher than that. He dials in a few one-thousandths of neck relief and keep the action at the nut as low as possible, too.

But go look at his article, it's much more complete that what I can recall off the top of my head.

[Bob Webster]

The question of what the action should be at the 6th fret actually begs the question of how much relief should be built into the bass side of the fingerboard to accomodate the larger amplitude of the E strings vibration, as well as to avoid back buzz behind the tretted note on that string.

If those are Kenny's numbers, they're a bit on the tight side, but excellent so long as some "belly" is left on the bass side of the fingerboard from the 1st through the 7th frets. Thereafter, it can be straight to the end of the fingerboard. It should also be noted that the clearance between the strings and the 1st fret should be on the order of 0.030" on the bass side, lowering proportionally to ~0.020" on the treble side. The result of all this is a pretty slick, buzzless action.

Cheers,
Bob

[Brent Hutto]

Bob,

The numbers Kenny gives concerning action at the nut indicate that he keeps it very low, less than 0.010" it seems. But what he actually gives are string heights at the nut of 0.052" to 0.056" and then refers to "...standard fret wire 0.045" (?) high..." [sic] when in fact the dressed height of that "standard" wire is most likely closer to 0.035" or so. So in my interpretation he is recommending in the neighborhood of 0.020" across the board but not actually recommending the totally unrealistic 0.010" that his misleading numbers seem to imply. I wish he had gone back and measured the (installed, dressed) fret height before finalizing that article.

His article says that .003" to .010" relief at the 7th fret is good with higher on the bass side but he doesn't get very specific. Then again if he has a truss rod it's a matter of "season to taste" if you don't like how it plays I guess. I think all guitars should have a truss rod.

[Bob Webster]

Yea, it does come down to fret height, doesn't it? If I remember correctly, StewMac's fret wire is about 0.038-39". Also, I wouldn't count on seeing alot of fret dressing on Kenny's guitars simply because setup, fingerboard shaping, and fret seating are all pretty consistently excellent. Still, all in all, a pretty tight action that, of course, might benefit at some point from a crank on the truss rod. Relief on the bass side of my guitars runs around 0.012-16" for the heavy handed artist (like myself).

Cheers,
Bob

[Steve N]

Bob and Brent,
Thanks, big time. This article is what I needed. I would feel ok about making a bone saddle, but not a nut. By the way, do either of you have any particular classical strings that you like. This Takamine classical came with D'addarios. If I know my daughter, she'll want to try a bunch of different strings.

[Bob Webster]

There are lots of exotic composites that she could try but D'addarios are just fine. The EJ45s are a medium tension string that has a very decent middle of the road response. I install them on all of my new guitars so that I can have a baseline for comparison with other guitars at the particular shop that I sell mine to, at the owner's insistence. Moreover, they won't break the bank. Savarez Blue/Reds are also a good set.

Just one caveat. Don't judge the strings or the guitar for at least 4 hours as it takes that long for them to reveal their tonal properties. Before then, the sounds you hear will likely disappoint. Patience has on numerous occasions kept me from slitting my wrists over what I was hearing. The difference is quite remarkable.

Cheers,
Bob

[Steve N]

Speaking of the classical strings - why would someone want mixed tensions? high tension bass strings with lower tension highs, or visa versa?

[Bob Webster]

High tension bass strings still aren't particularly tough to finger and the added mass can contribute to greater power and sustain and, some say, a little more complexity in tone. The vice versa isn't often done because the basses would suffer a bit. The use of high tension strings in the trebles is strictly a matter of taste and their effectiveness in promoting brilliance would very much depend on the construction of the guitar. On a lightly built top, they can actually choke the sound a bit.

Bob