Physiological effect of bass frequencies

You should be aware, that music (or rather sound) will have a physiological effect on the body if it exceeds a certain volume. The for a film composer great thing about that is, that your audience can not gain concious control over that. Especially loud bass frequencies will set our body into an alert modus automatically which is coming from the times when loud bass frequencies automatically meant a threat to us (thunderstorm, volcano, earthquake etc.). This stimulation is also part of the reason why club music tends to be loud and bass heavy. You can consciously use that effect when writing and producing film music by using bass frequencies to raise the level of tension, e.g. in thriller/horror situations (if you don’t do it, the sound design will probably do it. Just watch more recent thrillers/horror movies where in almost every “scary” scene, you will have a bass rumbling). But you can also use it to create that extra “oomph” moment in other contexts. This works even to a certain extend by bringing in double basses after a longer period of their absence.