At the beginning of the masterclass, Professor Blacher comments about sound clarity, and then they work on shifts and bow distribution, spiccato, and the relocation of the right arm to get a better sound.
He recommends color changes about the piano dynamics and, after that, they review the tuning and sound quality in certain difficult passages.
It is important that the student knows the harmonies is playing in order to be tuned with the piano. They also work on issues related to double stops, right hand and bow movement, etc.
Regarding the cadence, Professor Blacher suggests some string changes and other aspects of the student's execution.