I've been asked for many years, "Should I use round core or hex core strings?" "Which is better?"
Neither round core strings or hex core strings are better than the other. They are just different and they offer players
a choice in tone, feel, performance and installation.
All strings were round core until the mid 1970's.
Round cores are made using round shaped tin-plated, high-carbon steel wire (spring wire). Plain strings are made from the same wire.
When the round wire is made into a core wire and the ball-end is attached, the wire is swaged at a point on the wire where the cover wire can hang on to the sharp edges on the wire where the core wire is swaged. The swaged area on the core wire keeps the cover wire from unraveling before it is installed on a guitar. CLICK HERE to see how round core strings are made. Round core strings require special attention when installed to make sure the cover wire does not unravel. CLICK HERE to see how to install round core guitar strings.
Hex cores are made from the same type of wire as round core except is hex shaped which does not need to be swaged because the hex wire give the cover wire several sharp places to hang on to the entire length of the string. Hex core strings are easier top manufacture and easier to install.
There subtle differences in tone and feel between round core and hex core. Many players say that round core string feel like they have less tension than hex core strings. Our test show that there is virtually no difference in measurable tension, but round core strings can feel easier to press down on and the bends seem to be smoother with some players just saying round core strings just feel better the the tone seems to be a little wider with a more lively chime. Many hex core players say that hex strings have a tighter, punchier sound and that they feel more solid.
There is no wrong or right. They are just different.