MrAudioSoundImages's video: Roundwound Flatwound and Groundwound Strings

String instruments like guitars, mandolins, violins, basses, etc. and some percussion instruments like pianos, produce sound from the vibration of strings, which can be made of metal, nylon, silk, Kevlar, or gut and can either be plain or wound. In general, the lower strings on an instrument will be wound, in other words, have wire wrapped around the core to add mass and lower the pitch. Even some nylon strings are wound with steel, and some steel strings, known as tapewound, are wound with nylon. There are three categories for wound strings: roundwound, flatwound, and groundwound. With all three types of strings the central core usually has either a round or hexagonal cross-section. With roundwound strings, the central core is wrapped in a spiral with wire that has a circular cross-section. Flatwound strings will wrap the core the same way, but the wrapping wire will have a rectangular cross-section with slightly rounded corners. The advantages of flatwound strings are that they usually feel smoother to the musician’s fingers, they don’t make noises when musicians moves their hands on the strings, and they’re less abrasive to both the frets and fretboard. Besides the fact that they’re usually more expensive, the disadvantages of flatwound strings are that because the winding makes these strings stiffer, they generally don’t produce as many higher harmonics, so they sound duller than roundwound strings. Also, there’s less sustain with these strings, and again, because they’re stiffer than roundwounds, they’re not as easy to bend. Groundwound strings, also known as half round, start out as roundwound, but then are either ground down or pressed, so that the surface is smooth and have all the advantages of flatwounds, but also they have much of the brightness, sustain, and bendability of roundwounds.