A good violin should produce a rich, full-bodied sound that is clear and resonant. The sound should be well-balanced across the different strings and registers, and should have a good sustain.
The sound of the violin should be warm, but also have a good projection. The sound should be consistent when played at different dynamics and across different registers.
The tone should be even and smooth, without any harsh or "screechy" overtones. Additionally, the sound should be responsive to the player's technique and expression.
It's important to note that the sound of a violin can vary depending on the type of music being played, the acoustics of the room, and the personal preferences of the player.