Thanks ; I may try nylons .I never found the one I owned boomy at all, but we all have different tastes and perceptions. If its boomy to your ear try either Nyltechs or some type of strings. Both are more percussive and less prone to being boomy than either fluorocarbon or regular Nylguts.
I'm wondering if the KS-1 is any less boomy than the 5 ?Sometimes I feel that the laminate instruments, even those high quality ones have a bit of a boomy quality to them.
No , not a particular string .Is there a particular string that's boomy? I find the C string is often the culprit. If so, try a slightly thinner gauge C.