it's never been quite as simple as 'heavier gauge strings
sound better'. That's the trouble with Rules of Thumb, they are only a good guide so long
as you understand the assumptions behind them.
And with string gauges it gets
especially complex because you have to look at both the differences between light and
heavy strings AND how they interact with the guitar.
When you work from light
to heavy gauge strings (all other things being equal) you are doing two things. For any
given note you are increasing both the mass of the string and the tension. Both increase
the potential energy available when you pick or strum. That increased potential energy is
seen as increased volume and increased harmonic complexity. Or in other words, light gauge
strings have quite a pure tone with a string fundamental and as you get heavier gauges you
start to get a stronger contribution from the harmonics.
However, you don't get
something for nothing. As you increase string gauge it gets harder for the metal to flex
at the short wavelengths of the higher harmonics. The string will still generate those
harmonics, but because of the limits of the materials the harmonics go progressively sharp
relative to the fundamental. This is known as Inharmonicity. Essentially, the string is
out of tune with itself at the higher harmonics. Now, that isn't necessarily a bad thing
because it makes for a more complex and interesting tone. It can work very well with both
lead guitar and fingerstyle. But when you are playing chords, especially complex or
extended chords, that can mush out the bottom end and make the top end quite harsh and
Then you have to factor in the guitar, and especially the
front of an acoustic guitar. It's not a perfect analogy, but you can compare an acoustic
guitar with a guitar amplifier. The height of the saddle is the pre-amp gain, the front is
the EQ, and the whole body is the power amp.
The higher the saddle, the more it
amplifies the string vibrations. A light top with light bracing will vibrate freely, a
heavier top and/or heavier braces will damp the higher frequencies.
And just as
it is possible to overdrive an amp, it is possible to overdrive the front of an acoustic
And that's why you have to choose the right gauge strings for your
playing style AND each individual guitar. There's no 'one size fits all' option I'm
Hope that helps.
When the going gets weird, the Weird turn Pro.