30-string Contra-Alto update, part 2

The 30-string Contra-Alto guitar has been through some transformative changes in the past year or so.  I discussed some of the transitions in this blog post.

Back in January, I dropped it off with my friend Laurent Brondel to do a fret level on the 18-string side.  The 30 is now 14 years old, so it was time.  Laurent does beautiful work, and is one of only about two or three people in the world I'd trust to work on one of my instruments.  I picked it up from him this week.  

The frets were not only leveled, but also beautifully crowned.  The crown is the top surface profile of the fret surface.  Imagine in the fret side-view or cross-section that the top of the fret surface is arched or in a half-circle.  That's how a fret should be crowned.  In other words, not flat and squared-off on top, but perfectly arched and rounded.  The proper crown accomplishes a few things:

• Improved intonation.
• Cleaner fretting in terms of sound and technique.
• The action feels better, or in some cases, feels lower, as you're no longer fighting with the uncrowned fret edges.
• Cleaner and more precise string-to-fret contact.
  

The perfectly leveled frets enabled me to lower the action a bit.  As the action gets lower, the levelness of the frets becomes more and more critical.  If the frets are not level, you're not going to be able to get the action lower.  When I dropped it off with Laurent, the action was as low as I could get it at that time, which measured a bit above 1.5/32" of an inch.  This limitation was due to the non-levelness of the frets.

There is more than one way to measure action; each guitarist that I know uses their own method and swears by it.  I don't know that any one method is better than any other; I think we as guitarists gravitate toward the method we know.   My method is to fret the first string at the first fret, and use a stainless steel machinist ruler to measure the distance from the top of the 13th fret to the bottom of the first string.  I use the same method for measuring the action on the lowest string, as the bass-side strings require a bit more height than the treble-side strings.  1.5/32" is pretty low action, but I still felt like I was fighting it a bit; most of my other instruments have a slightly lower action than this, and when you play an instrument with action higher than you're used to, and higher than optimal for you, you really notice it.  It can be a hindrance to your playing, so it's key to get the action where it's optimal for you.  Action is a very personal thing and is different for everyone.

The 18-string side of the 30-string has a split saddle: the first five courses have a saddle, and the lower four courses have a saddle.  I'll refer to them as treble and bass saddles for now.  The treble saddle had been shaved, and required two saddle shims: one at .016" and one at .004."  I use brass or stainless steel shims for the carbon fiber instruments, and ebony shims for the wood instruments; the shims in the 30 are brass. 

This morning, I removed the .004" shim, and using the truss rod on the bass side, removed the remaining relief in the neck on the bass side.  .004 of an inch doesn't sound like much, but in this case, it's the difference between having a playable or unplayable instrument.  If the action is too low, the strings fret out, which means you don't get actual musical tones and notes from the strings; you get a pitchless rattling buzzing sound.  Unplayable.  Now that the frets are leveled, I dropped the action a bit, and it's now measuring just a little more than 1/32" on the treble side, and about 1.5/32" on the bass side.  This is about as close to perfect action as I can get.  Pretty exciting.  The 18-string side feels entirely different, and is greatly improved.

I also went to lighter string gauges on the first two Contra courses.  These are both unison courses, so the string gauges for both strings in the course are the same.  Previously, the courses were at .015 for the high C,  and .018 for the high G.  I changed those to .013 for the high C, and .015 for the high G.  The courses now have a bit more of a singing quality, less of an emphasized attack, and a bit more clarity.  They also feel better with the lighter gauges for legato playing techniques.  I'm usually a proponent of heavier gauges, but for the 30 and for these two highest Contra courses, going lighter was the right option.

I've also moved from a phosphor bronze string set to an all-nickel string set for the 18-string side.  Lower tension, and I find the all-nickel set to be a bit more responsive with greater clarity and definition.

While the 30 was at Laurent's, I asked him to look at the nut on the 12-string side.  The action was pretty good on the 12 side, but was too high coming off the nut.  I can and do re-slot nuts, but I didn't want to this time, as I wanted Laurent to see the entire instrument and get a sense of its health before any changes were made.  The frets on the 12 side didn't need to be leveled, but he agreed that the nut slots were not deep enough.  So, he reworked the nut on the 12 side, and it also feels vastly better and is easier to play.

All quite exciting. Going forward, I'll be using the 30 more than ever. 

-kk