For a more in-depth discussion of improvisation as it applies to the technique and interpretation of classical music, see Jonathan Sturm, “Improvisation: Bringing Performer and Instrument Closer Together,“ American String Teacher Vol. 40, No.3 (Summer 1990): 56-58.
2.
A clue pitch is essentially an auxiliary note heard only to the performer during a shift. It ultimately sounds as a whistle tone, because the finger sounding the clue pitch does not weigh heavily enough on the string to connect the string to the fingerboard. Clue pitches are practiced first as sounded auxiliary notes to establish their importance and locate their placement. Then they are gradually faded away by decreasing finger pressure and bow weight during shifts until the shifts sound musical to a listener; the performer still has access to the information that the clue pitches provide about the finger's location on the instrument relative to where the shift will end.
