Mailbag Q: Why are there metal strings on a classical guitar?

I get asked this question now and then online and in-shop and a reader emailed me this question in regards to his Harmony classical from the '60s. If you know about this sort of stuff, you know about it. If you're green to nylon-strung instruments, you're wondering the same thing.

The short answer is: there aren't really metal strings on it.

Classical guitar strings, in general, consist of three "wound" bass strings and three "plain" treble strings. The "plain" strings are single-filament (one piece) nylon or fluorocarbon material, usually.

The "wound" bass strings use stranded (rope-like) thin nylon filaments to make a "core." This "core" is then wrapped with another material to give more mass to the string. Adding mass to the string means that it sounds at a lower pitch compared to the "core" on its own which would act more like one of the "plain" strings.

One can get this extra mass in many ways, but since at least the Renaissance (correct me if I'm wrong, please) it's been common to use some sort of metal wire to wrap around a "core" string (stranded or solid) to add this mass. Metal (usually silverplated copper for classical strings) is durable and consistent as a wrap material.

It was also common to see gut "wrap" over gut "cores" in times past to get to a lower pitch and that's replicated by some Mexican and Central American string makers for traditional instruments of the region by wrapping nylon "tape" over nylon "core" strings. This can be found on some American-made upright bass string sets and the gut-over-gut approach is relatively common in fancy upright bass strings, too.

The other short answer is: don't worry about it.