Selecting the right string gauges for alternative
tunings. You can drop light-gauge
acoustic strings (.012-.054) down a whole-step but beyond that, they don't
have sufficient tension to make the guitar resonate or stay in tune. Medium-gauge
strings (.013-.056) give better tone and response for lower tunings. If you
drop a fourth (B, E, A, D, F#, B) or fifth (A, D, G, C, E, A) into the baritone
realm, you might prefer the tone and feel of heavy-gauge strings (.014-.058).
Usually, moving to heavier strings calls for
tightening the trussrod, although looser, heavy strings won't necessarily
create more tension than taut, light ones. You'll have to restring your guitar,
choose your tuning, and observe the results. Thick, looser strings tend to
rattle against the frets, so a little neck relief (bow) is good. If there's
too much bow, however, tighten the trussrod a bit. Go easy, retuning and checking
the relief over the period of a few days.
Scale length and Intonation.
Standard acoustic guitars, scale-length typically runs between 251/8"
and 25.4".They are designed to play in tune at or near concert pitch.
Low-tuned strings won't fret in tune all along the fretboard. The fifth and
sixth strings, which sound increasingly sharp as you ascend, are the worst
offenders. You can improve intonation problems by moving a low-tuned string's
saddle back (away from the nut), which will increase a string's vibrating
length. Most flat-top saddles aren't individually adjustable, so you'll have
to shape a new one. Fitting and intonating a saddle is tricky, but replacement
saddles are inexpensive. You can always return to factory specs if you keep
your original saddle unmodified and perform your surgery on new saddle blanks.
The goal is to move the string's break point to the rear edge of the saddle.
You accomplish this by filing away as much material as possible on the fretboard
side of the saddle. A points plug file (available at automotive stores) works
well. You'll want to maintain an even height on all strings while filing a
gentle curve that follows the fretboard radius. The three bass strings should
ride a tad higher than trebles. Take the time to restring frequently and check
your progress. When you're satisfied with the action, and have created a narrow,
even ridge along the rear of the saddle, polish the top with emery cloth to
remove any rough edges. The surface where the string contacts the saddle should
be smooth.
