The first part of this theoretical masterclass is about sound quality. Professor Geringas suggests that the first step to avoid an "ugly" sound lies in admitting it, then it is necessary to take care of the bow speed, weight and movement so that the strings can always vibrate. They work on the cello position to achieve this and Professor Geringas proposes to the student an exercise to improve the quality of his sound.
The second part of the masterclass consists on explanations referred to dynamics: not to consider it as something absolute but relative because it depends on its context. As an example, David Geringas mentions the Ligeti Concerto. He also talks about acoustic issues and the difference with the electric cello - Prof. Geringas plays the beginning of the Adagio and Allegro, Op. 70 by Schumann. Geringas suggests thinking about how the sound spreads outside and not how is the sound inside the cello.
To conclude, the professor compares this with the gestures of a conductor.