My friend and I were disputing about if someone installs another instrument's strings on a different instrument such as: (guitar strings on harp or vice versa, Oud strings [an oriental instrument] on guitar, piano strings on guitar, and so on...)
Would the new setup-instrument produce its usual sound with slightly difference in notes pitch or would its sound be totally different and just similar to the instrument which we took the strings from ?
In more general view, what is specifically the main factor that characterizes the sound of an instrument to be its own sound ? the sound box shape ? the strings material ? strings length ? strings tension ? or what ?