Mozart music style, violin

Today I heard 2 students playing Mozart concerto. 2 different ones. Both can manage the notes relatively well, but both are not playing with the correct tone color, and articulation.

In order to appreciate the Classical period style, the best way would be to listen to more recording. Mozart's music is lively and charming enough for most students to like. And to learn. At the same time, the music demands high clarity, crystal clear tone, that remains challenging even for advanced players. This is especially so when a bunch of them are going to play together, as in an orchestra music. It remains a "test", or a "measuring rod", for an orchestra to perform anything by Mozart. No doubt the structure of the music is straight-forward. Layers of phrases, melodic lines, etc. are simple. Precisely because of that, it is challenging for 70+ players to execute with identical articulation, despite difference in instruments (most prominently in the first violins).

Let's see if those 2 students can make improvements.