Strings in Playing Mountain Dulcimers Posted May 12, 2020 I've read a few accounts of trying nylon strings on a dulcimer. None really worked out well because of the way dulcimers are generally constructed. The strings are usually attached to tail block and the scroll/peg head. On instruments like a classical guitar or ukulele they're connected to the soundboard and the soundboard vibrates freely. Or on a violin they cross the bridge that vibrates the top plate directly. Nylon strings are much lower tension than steel strings and will have lower energy when you strum them. On a dulcimer you'd get a very weak sound. Aaron O'Rourke has some videos of a nylon string dulcimer, but it's a prototype specifically constructed for that purpose. To your other question: Higher gauge strings will increase tension and tend to be louder. They may also produce a warmer / darker sound than lighter gauge strings. Due to higher tension they'll require some more pressure to press down. Changing string tension can also affect intonation. With higher tension, it requires more pressure to fret a note. When a note is fretted that pressure also slightly changes the string tension. On an instrument like an electric guitar, the saddles on the bridge are adjustable to account for this. Most dulcimers don't have an adjustable bridge, and if they do it's usually a single piece. Unless you change it significantly it's not likely to be a problem, but it's something to be aware of if you change the strings and the intonation is off.