I am relatively new to classical bass playing, after a few years of jazz (both upright and electric). One problem I've encountered is how much rosin to use. I believe I may have been using too much recently, as there is a "screechy" undertone to my sound, and the bow often seems to glide too freely across the strings. (and I'm positive that too little probably isn't the issue) Exactly how much rosin is correct, and how can I go about fixing my current problem of too much rosin on the bow? Thank you!