The CH Guide  To   Sound Design  

17th April 2020 by CH

What  I s Sound Design ?  

Sound design for video is the acquiring, creating, combining and manipulating of audio to accompany and enhance the  all-important  visual s .   Sound is  often  an  overlooked  part of the video-making process but it  has the ability to make or break  a project .  

Types of Sound  

The types of sound in  our  videos can be categories as  either  speech, music,  or  sound effects.  

Speech  is  usually either  recorded along with the footage, such as an interview or  piece to camera, or as a voiceover.  It is  almost always  used as the main  method  to  deliver  the  message  being  illustrated by the visuals.  

Music  for our videos is most often taken from royalty-free  stock  music libraries.  These tracks   can be used for as long as needed, wherever  it’s need , whether that’s a   TV advert, online video, or internal communication.   U nlike royalty-free music,  use of  a  pop trac k  owned by a record label   require s   permission based on how it will be used and for how long  and is usually a lot more expensive!  

We  browse  and   handpick the  tracks that best express the mood of the video and  can be edited to help deliver the message.  This will involve cutting up the track, looping certain sections and cutting others to create the right  length and  momentum for the edit.  

Other than speech or music,  there are  s ound effects . These can be natural  sounds   such as footsteps ,  or unnatural  sounds  such as  filtered noise.  Foley   is a term used for  recorded  natural sounds added to a scene such as mouse clicks, chairs squeaking and  clothes rustling . It can give more life to objects  and  people ,   and draw  the  viewers’  attention to certain actions.   We have  our own  large  collection  of sound effects we choose from as well as browsing  online  libraries  to find that perfect whoosh to give weight to  that text transition, or ambience to  fill  that office scene.  

Diegetic vs. Non Diegetic  

One of the simplest ways to talk about how sound is used in a video is  diegetic  versus  non-diegetic   sounds. Diegetic sounds are those of objects or people visible within the scene such as the voice of a person talking to the camera, leaves rustling through trees in the background, or music coming from the annoying party next door. Examples of non-diegetic sounds would be voice-over, music not coming from the scene ,  and sound effects added for dramatic effect.  

Certain sounds can be  trans-diegetic  meaning they move between the two. For our interview-lead videos we often start with someone on screen talking which then becomes the voiceover as we cut away to b-roll footage. Another example might be music that we see being played by a musician before we cut to a different scene as the music continues and builds underneath to become the  score  for the video .  

Audio  E ffect s,  E diting and  M ixing  

Once the perfect piece of audio has been inserted into the project, e ffects  are often used  to change  the sound . Three common examples are  reverb ,  compression ,  and  equalisation .  

Reverb simulates sounds’ reflections off surfaces and  can create a sense of space, transporting hollow  foley  footsteps recorded in a studio to a lively stroll through a large auditorium.  

Compression evens out the sound by squashing down the loudest parts, before bringing the volume back up. This gives voices in particular a thick, powerful sound, which can make  an  interview or voiceover sit  comfortably  on top of  music and sound effects .  

Equalisation, or EQ, is used to control which frequencies of  the  audio are loudest. For example ,  if  a  voice sounds muffled the low  to  mid frequencies  can be reduced  and  the  higher ones  increased , creating a brighter sound.  

We also  often use effects such as  denoisers  which intelligently clean up audio, for example removing background noise from a recorded voice .  

When  D oes  S ound  D esign  H appen?  

Sound design is often a part of the whole process of editing  as audio is usually needed from the start, whether to edit together a voice-lead video, or to  dictate the rhythm for a motion graphics explainer. That being said  it’s best to leave the final  polish   until the visuals are in place , ideally alongside the colour grade .  

How  L ong  D oes  I t  T ake?  

The length of time sound  design  require s  in a production varies hugely.  It can take an editor a couple of hours to add  in some music , a couple of  sound effects, even out the volumes and  push it out the door. On the other hand, to create  a complex music edit  that perfectly complements the visuals , with  a  rich texture of sound effects  and foley could take days, or much longer.  

Mastering  

The  very last step in sound design is checking the overall  audio output, rather than the individual sounds.  For certain applications such as TV broadcast,  there may be strict standards to adhere to when it comes to  volume  level  and loudness across the video. For web-based videos it’s a bit more of a wild   west but at CH we have our own standards to ensure the video  will sound brilliant and clear, wherever it’s played.  

To find out more from us, just say hello@ch-video.co.uk