Problem when changing tunings
Q: Hi there from Scotland!!
I've just had my 23-year-old Martin MC-28 refretted,
new nut and set up by the authorised repairer.
I use Martin Phosphor Bronze light gauge strings and it sounds
when I detune (especially in DADGAD tuning), the B string sounds
duff!! The other strings are fine.
Should I put a kind of shim either under the nut (which is
floating) or under the saddle, or should I leave it alone?
The repairer told me that all sorts of problems arise when
tuning down, especially with light strings.
My mate's guitars sound fine with extra lights, so what do
Shall I leave it well alone, or shim it?
Should I shim it at the nut or saddle?
What could I shim it with?
Thanks for your time.
A: By "duff" I presume you mean that
it's buzzing. Rattling
against a fret or two. You have roughly 25 pounds of tension on
each of your strings.a total of 160 pounds of string tension with
light gauge strings (look on the package of a set of D'Addario EJ-16s
for exact figures). When
you lower the E, B, and high E a whole step each, you have removed
at least 10 pounds of pull.
Your neck is not rigid.
It is planed with exactly enough bow back so that the recommended
strings and tuning will pull it perfectly straight.
If your MC-28 had been made after 1983 all you would need
to do would be loosen the truss rod a tad.
Unfortunately you have no truss rod so a simple neck adjustment
involves pulling the frets, planing the fingerboard and driving
also said that the B is the only string that buzzes when you go
to DADGAD. So you need
to check to see if the string buzzes against the first fret.
Then put your finger on the first fret.
If the string does not buzz against the second fret, your
nut is too low. The
nut height only controls whether or not the string buzzes on the
first fret. If it buzzes
anywhere else it is not a problem with the nut.
If the B slot in the nut is too low it can be filled with
bone dust and super glue and refiled.
This works perfectly with bone nuts.
Your original nut was made of Micarda and the super glue
doesn't always stick. Hopefully your new nut is bone.
string is buzzing on one or two higher frets you need your frets
leveled. If it buzzes
evenly all the way up you can just raise the saddle. You need a
solid connection between the bottom of the saddle and the bottom
of the saddle slot. If
you try to shim one end you will leave a gap.
You can put a hard wood shim all the way across and then
reshape the top on the saddle so that only the B is raised. Remember
that the 12th fret is the halfway point of an equilateral triangle
with it's apex at the nut and it's base defined by the amount you
are going to change the saddle height.
If you want the string to move 1MM closer to the 12th fret,
you must cut 2MM off the saddle.
If you want to raise the B string 1/32" at the 12th fret
the saddle must go up 1/16".
know what you mean by a floating nut. The saddle, in the bridge
is not glued down. It's
held in place by string down pressure.
Nuts are always glued in.
Is the nut/saddle terminology switched in Scotland?
that if you took your guitar back to your luthier and asked him
to adjust the guitar for DADGAD he would be pleased to do it.
But then, when you tune back up to standard, the action will
be higher than perfect. The
fact that only your B string buzzes may mean that the others are
already higher than necessary.
I would give your luthier a second chance on this guitar.
It often takes two tries
to get an action right. Sometimes
the tension has been changed so much that it takes the guitar a
few weeks to get used to the new load.
Sometimes the luthier doesn't have a clear idea of your style
and gives you a generic action.
When you say "no, higher/lower" he will nail it on the second
ultra light strings. They
are just wrong. You
must use them on very old, very small guitars, but they don't have
the mass to move the top of a modern guitar.
Have your friend try moving up to light gauge.
If they hurt his fingers, he needs an action set.
If by "Duff"
you mean that the string is weak and floppy sounding? The pitch
of a string is defined by the length of the string, the mass of
the string and the tension on the string.
The pitch is changed by varying any of these three factors.
You can raise the pitch
by making the string thinner, tighter or shorter.
A string must be pulled to about 80% of breaking tension
to make it "sing". To
make it act more like a fluid than like a rod.
A light gauge B string is a .016.
They sound great pulled up to B. Tuned down to A,
a .017 might sound better.
Some serious DADGADers use, from the top:
.013, .017, .024, .034, .044, and .058.
Some have a different guitar for every tuning they use.
If you must use the same guitar for lots of tunings have
your luthier adjust the action for the tuning with the lowest tension.
When you go to the higher
tension tunings the guitar will be harder to play.