Got any idea how many sound effect a recent FPS game requires? Take just a simple aspect of the game: a weapon. Most games have those. suppose you have 5 guns, you'll need 5 sounds, right? Think again.
You will need:
- A sound for when you draw the weapon out of the holster.
- A sound for when you pickup the weapon, another sound for when you drop it.
- Several good sounding sounds made by the weapon itself when used to attack. Different attacks, different sounds.
- A sound for reload, when it applies.
- A sound when you hit the target, a sound when you hit a wall, and so on. Different surfaces = different sounds.
- If the weapon does other stuff, like getting jammed, you'll nit more sounds for that.
- And so on and so on.
Creating all those sounds can often be a tedious and repetitive process. Just because there is audio involved doesnt mean that its all fun and games. Having the right effect by simply recording the right object bumping into something rarely does the trick by itself. You'll need to shape the sound, add effects, layer several sounds, etc. All of this takes time.
The project I'm working on (can't give much details atm) calls for about 140 original sound effects and 12 bits of music. That's at least 100 hours of work. With a full time job, I can still spread that work in about 20 weeks at 5 hours per week. That's about 4 months. Should be done by christmas!