Something that is not widely known.

Most players set up the instrument so that the string presses down firmly on the wheel - this gives the familar 'scratchy sound'. My dad was a violinist - I understand about 'bowing'.

I set mine up so that the wool - real wool works better than real cotton (and don't get confused with man made 'cotton-wool') provided you can get good quality wool - is loosely around the string. The string is adjusted so that the string _cannot_ touch the lightly rosined wheel at maximum amplitude: the wool 'bundle' is the only contact with the wheel. This gives a pure tone with no scratchiness, like a properly played violin.

Simple really, but most people seem to WANT that horrible sound!