Some directors just sit back and don't care much unless something sounds completely wrong. The effects are then mixed in with the voices and music. This process is called dubbing and we usually refer to it as just DB . Dubbing can take a long time. If things don't work well it can take a day.
Movies take a much longer time because they usually have much more complex soundtracks.
The sound engineer is the one who is in charge of the technical end of sound. They are the ones who know what all those little multicolored knobs on those fanatically complicated mixer boards really do. The voice actors. The vast majority of Japanese animation is done with afureco, or with the voices recorded after the animation is done. The voice actors watch the action on a projection screen and perform their lines to it.