I can tell you from experience that when a timing belt breaks the only sound you hear is the sound made when you toss a small stone against a fan blade. The sound is so short in duration you might have missed it.

If the timing belt broken, when you try and start the engine, the engine will turn over very fast. If the engine turns over like normal then you have some other problem and you should thank you lucky stars.

As stated in the earlier post, the valves are trashed when the timing belt breaks. Pulling the head will reveal dents in the pistons. Just a sicken sight to be sure.