Don't settle for one sound. Layer a sharp gasp over a low murmur to make the crowd sound larger and more realistic.
If your scene is in a hall or stadium, add a "Large Hall" reverb effect to the sound clip so it fits the environment. udivlenie tolpy zvuk skachat
The reaction should usually hit about 0.2 to 0.5 seconds after the surprising visual for a natural feel. Don't settle for one sound