Julia Bushkova's Violin Class videos
Absolutely wonderful -- beautifully explained and in ways I haven't seen elsewhere
"With Nicky" (Nicola Benedetti)
Very comprehensive, very professionally done series covering essential techniques from a holistic point of view. It is obvious that Nicola Benedetti takes teaching very seriously -- the videos are pedagogical
Violin Masterclass with Kurt Sassmannshaus
Most comprehensive series of lessons across different topics with videos and notes
Video compilation of examples of vibratos of great violinists at normal speed and then slowed down
Maxim Vengerov Masterclass @ Blackheath Halls, London, UK (1998)
master of musicality and interpretation
The Heifetz Masterclass Series @ USC, California, USA (1962)
Masterclass with Glenn Dicterow @ The Music Academy of the West, California, USA (2017)
strong pedagogy
Masterclass with Ray Chen @ AYO, Brisbane, Australia (2014)
nice mix of advice on technique and musicality