Sonic force: Jim Griffin, Owen Griffiths, The Jungle Group

Whether it's a voiceover, sound effect or music, the audio element of a campaign - when designed and planned effectively - can have an enormous impact.

Sonic force: Jim Griffin, Owen Griffiths, The Jungle Group

Sound can affect us in many ways: it can annoy, soothe, make us feel happy, sad or frightened. Almost any emotion can be provoked in us by the right noise or combination of sounds.

From the moment we're born, we start to build up a set of responses to the noises we hear, and begin to associate sound with experience and emotion. At Jungle, we've been helping advertisers understand this synergy for almost two decades.

Advertising is a very precise discipline where every frame counts, and it is important to get the picture and sound right. When considering sound, there are three elements to think about: the human voice, sound design and music.

Everyone is familiar with voice. We all talk, we all listen, and we all perceive very subtle nuances within another person's speech. In the same way, every inflection and stress within a voice edit makes a difference to how well it conveys a message. Very experienced actors are often surprised at the level of detail that goes into assembling a final voiceover edit.

A great deal rests on casting, so it is important to discuss voice options before a booking. It also pays to have an engineer able to help with direction. They should be able to subtly point out and remedy any voiceover ailments such as "gob-clack" or "Mic-munching". And there's no substitute for taking a script and reading it at a calm pace against the clock. This should allow the actor to concentrate on getting a good performance, and not racing to finish.

The art of sound design lies in knowing how to record, select and manipulate sound to paint a picture for the audience. It completes the picture, adding the necessary dimension to bring what you are seeing to life.

It's often said that you don't notice a football referee if he's having a good game, and generally you only really notice sound design if it's done badly. Done well, it tends to pass unnoticed, leaving the audience with the perception that the overall quality of the film is better.

Of course, sometimes sound is the hero. When the visuals call for a dramatic noise, design can really come into its own, increasing the impact of each shot. The ongoing Lurpak campaign and the current Carnival Cruises TV spots illustrate this well.

So how do you decide on the approach? It's a good idea to establish the appropriate style of treatment from the outset, in order to avoid costly misunderstandings later on. Even if it appears self-evident, consider the texture the sound needs to take at an early stage, and plan what will be best recorded on the shoot itself.

Sound design can help the audience believe what they're watching, and enhance the visuals. It can also give you some of the colder reactions, including unease, shock or revulsion. But to make the audience feel more complicated and deeper emotions, you need harmony or dissonance. You need music.

The rules of music have been developed and refined over thousands of years. While our individual tastes affect the way we react to harmony and discord, there are some universal truths that we can make use of.

For example, the difference between a major chord (happy) and a minor one (sad) is only one note, yet we all appreciate the change of mood. A rhythm played at a higher speed than our resting heartbeat will make us feel on edge and exhilarated, whereas a lazy rhythm will make us relaxed.

The power of music lies in its ability to effect an emotional response, and advertising is more powerful when this happens.

For a commercial to work best, it should flow with the music. Sometimes edits deliberately work against the beat, but even then, they are conscious of it. When the picture and music are working well together, the overall effect is immeasurably improved. Get the choice of music right early in the project and everything else falls into place. It's surprising how a particular sound-effect treatment will work with one piece of music, but not another, because the harmonic content works differently in each case.

In fact, if you're working with a big music track, sometimes it's appropriate to design the sound so that it feels like it comes from the same place. In the studio, we often work to create a palette that has the same sonic characteristics as the instrumentation in the music track.

That crossover of musical and sound design is well established and we're lucky to have a music department, which can be working on musical cues while the rest of the session is going on.

The impact sound has in commercials is always massive, even if it's subtle. The trick is to spend the time and have the right conversations early enough to make sure that you maximise its impact.

Jim Griffin is a sound designer and Owen Griffiths is a sound designer and the director at The Jungle Group

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