part 2: the mix

guest expert: andy, sound designer and board director at 750mph.com top audio post-production company in london

producing an engaging soundtrack is, as many would argue, 50% of the film. in order to entertain your audience they have to be able to hear clearly all the things you want them to hear, just as the lighting and editing help them to see want you want them to see.

so your sound needs to be clear and of an appropriate level for your audience to enjoy.

compression

audio compression is one of the most useful tools available to you that will enable you to create a good, clear soundtrack.

fig. 1:

the audio in fig. 1 is highly compressed (this is dynamic range compression – not to be confused with digital signal compression, like mp3 or m4a).

this audio will sound loud (possibly too loud) and be very energetic. the average level of the audio is very high. many dance tracks or highly compressed tv ads are mixed this way.

a mix like this could risk annoying your audience and might suffer intelligibility on a large playback system.

fig. 2:

the audio in fig. 2 is much less compressed. its clear to see the average level or energy of the signal is much lower than in fig. 1. this audio will probably sound quieter than the audio in fig. 1 but, if it's well recorded, will have a more natural or “open” sound quality.

fig. 3

the audio in fig. 3 is clearly the quietest of the 3 examples, and is probably too low, and might lack crispness.

bearing in mind all these examples it still a good idea to exploit dynamics - that is having passages that are quiet and ones that are loud. there is no one way to mix a movie, but it is helpful to know you are mixing to the levels you intend.

you can find software compressors in most pc or mac based audio packages and it is definitely worth you while learning how best to use them.