Contact Core Guitar Strings

Craig 'Lumpy' Lemke BSEd, MA

"songthief"

RotoSound, GHS and perhaps a couple of other string makers,
produce a string with what is known as "contact core" design.
It means that the windings, on the bass or wound strings, don't
go all the way to the ball end, like more traditional strings.
With contact core strings, the windings start on the string itself,
not at the ball end. The result is that the portion of the string
that comes in contact with the bridge saddle is the core wire of
the string. In more traditionally made strings, the windings contact
the saddle.

Lowered Action with Contact Cores -

Since these are contact core design strings, there is
conceivably a tiny bit of change in the action on most
guitars. The strings, at the bridge saddle, don't rest
on the windings like traditional strings. Instead the
windings begin a little bit in front of the saddle. The
core wire of the wound strings therefore rests on the
saddle. That means that the wound strings sit a tiny bit
lower than traditional strings. The plain strings, 1st
and 2nd, are in the same place as any plain string.

Here are the measurements for the 3rd through 6th strings.

3rd string sits 0.0055"(or .35/64)closer to the soundboard.
4th string sits 0.008" (or .5/64) closer to the soundboard.
5th string sits 0.0135"(or .85/64)closer to the soundboard.
6th string sits 0.0185"(or 1.2/64)closer to the soundboard.

Those are tiny measurements, obviously. I measured them
in decimel inches with a micrometer and then also listed
them in 64ths of an inch since that is the traditional
luthier's measuring increment.

To figure the amount of change in action, we have to
cut those numbers in HALF. ie if the 6th string is
1.2/64ths lower at the bridge it is 0.6/64ths lower
at the 12th fret. Rounding that off, let's say it's
about half or a 64th.

Still with me?..;-)
Half of a 64th is pretty darn small. All but the absolutely
lowest action guitars can handle that with no problem at all
and will likely serve to make your conceived fretting just
a tiny bit easier.

Just a little stuff to think about for the overly
intellectulalizable, engineer types..;-)

Tone Differences with Contact Cores -

Because the core wire of the wound strings is in
direct contact with the bridge saddle, expect to
hear the tonal response of the guitar shift toward
the treble side.

If you're playing a Martin, for example, and you install
a set of contact core strings, expect some of the characteristic
"Martin Tone" to diminish and move toward what some might call
the "Taylor Tone".

If your guitar, with traditional strings, is a bit muddy
or doesn't stand out in the mix, installing contact core
strings might just brighten it up enough to make your tone
blend better.

If you're playing in a combo with other instruments or if
you're accompanying yourself (or someone else) while singing,
the shift toward bright might help make both the guitar and
the other instruments (or voice) a little more separate.

Volume Differences with Contact Cores -

Expect a little LOUDER sound from contact cores. The string
vibration is more directly transferred to the saddle. It's
not being dampened by the bronze/brass windings. So more
of the string movement is being used to produce sound.

If your guitar is equipped with an undersaddle transducer
pickup, expect the signal to the preamp/amp to be "hotter".
A hotter (more powerful) guitar signal should result in
less "noise" in the signal. Any noise (hum etc) that was
present is still present. But you've now made the desirable
signal louder which tends to overpower the noise. You should
be able to use LESS overall gain in your signal path, by
a small but noticeable difference.

Bottom line -

Switching to contact core strings will tend to result in:
- Lower Action
- Tone shift toward the treble
- Increased volume

Now get out there and play your guitar!

Craig 'Lumpy' Lemke - eBay songthief