More often than not, I can't find a .09 string when I need it!
Old strings can get floppy even if they were the right size back in the day. I can relate ;-)
Thanks lisa for the info.
The nut & bridge look fine and since the 9 should fit snug I wonder if the 10 or 11 string maybe wouldn't fit. Only way to tell, is to try. The 9 just seems loose, could be it's just time to change out the strings anyway. Why did you go with a 10, did you not have a 9 or just wanted to have it a bit heavier? I may try the 10 first, to make sure it fits. A new string maybe all it needs.
Other than that, I do like this dulcimer. It packs a lot of wonderful sounds
I have a Bill Berg 5-string hourglass that measures 27-1/2" from nut to bridge. Bill recommended these string sizes:
The wound bass string is on the outside. For the inner string on the bass course I often use a .10 instead of a .09 and it works fine. You can try .11 if you want, but I don't think string size is your problem. Bill knows how to set up a dulcimer and I am certain your MD did not leave his workshop with string interference.
Ken's right that changing strings is the first thing to try, since it's easy. But I'm wondering: does your MD have the original nut and bridge? Have they been damaged? If somebody took a file to the bass slots (perhaps to install a second wound string instead of a thin octave string) then they could have messed up the string spacing. The .09 string should fit snugly in its slot. If you can, post a close-up photo of the nut and bridge.
Rarely do I pass up an opportunity to suggest that people learn how to strum with a lighter touch, but unless you're strumming like a gorilla that isn't your problem; it's the dulcimer's problem. :-)
I checked against the Strothers String Calculator (known to be "light") According to that you should have
D = 19w; d= 10, A= 13
But since that is light, I would use D= 22w or 24w, d= 11; and A = 14
The D and d octave couplet may indeed be hitting each other occasionally since that .09 you have is so floppy. Change strings before trying anything else.
I have a 5 string, elliptical long scale BERG dulcimer
Question: It has 2 base strings:
The heavier string is the outside string, the thiner string inside next to it.
Sometimes I feel they are hitting themselves from the strings vibration;
String gauges on it now:
.024 for the wound bass string
.009 the string next to the bass string
.013 the middle string
011 for each of the two melody strings .