Achieving that Olde Tyme Sounde
So you're looking for that traditional "high silvery" sound. Your favorite builder creates a more traditional size instrument, but when it arrives, it still doesn't meet your sonic expectations. What's to do?
One thing I've discovered is that if you replace your wound bass string with a thinner, non-wound one, you get much more of that silvery sound. That big, fat wound bass string whipping back and forth pushes a lot of air around, creating more bass/baritone effect than a thinner un-wound string, even though tuned to the same note as the thinner string.
My Olde Tyme dulcimer is a no-name vintage shallow three string hourglass with a 27" VSL. It carries an 18 ga. plain steel bass string and 11 ga. plain steel strings for the middle drone and the melody strings. Much more silvery sounding than when I tried a conventional 24W bass string to replace the 18 ga plain steel original.
Anybody else tried replacing their wound bass with a thinner plain steel string?? Any good string gauge calculator can tell you the appropriate un-wound gauge needed to get the same tuning as you use for your wound bass string (C, D, G).
Another thing I've found is that tuning to a true key of G - GDD or GDg etc. gives a more silvery sound. Not the tuning for your dulcimer club gatherings, but really nice for solo playing.