Like most video editors, audio mixing isn’t necessarily my forte, but there are plenty of projects, where I end up “playing a mixer on TV”. I’ll be the first to recommend that – budget permitting – you should have an experienced audio editor/mixer handle the sound portion of your project. I work with several and they aren’t all equal. Some work best with commercials that grab your attention and others are better suited for the nuance of long-form projects. But they all have one thing in common. The ears to turn out a great mix.
Unfortunately there are plenty of situations where you are going to have to do it yourself “in the box”. Generally, these are going to be projects involving basic voice-overs, sound effects and music, which is typical of most commercials and corporate videos. The good news is that you have all the tools you need at your disposal. I’d like to offer some ideas to use for the next time that the task falls to you.
Most NLEs today have a decent toolset for audio. Sony Vegas Pro is by far the best, because the application started life as a multitrack DAW and still has those tools at its core. Avid Media Composer is much weaker, probably in large part because Avid has put all the audio emphasis on Pro Tools. Most other NLEs fall somewhere in between. If you purchased Apple’s Final Cut Studio or one of the Adobe bundles, then you have excellent audio editing and mixing software in the form of Soundtrack Pro or Soundbooth.
Mixing a commercial track that cuts through the clutter employs all the same elements as creating a winning song. It’s more than simply setting the level of announcer against the music. Getting the voice to sound right is part of what’s called getting it to “sit right in the mix”. It’s the same concept as getting a singer’s voice or solo lead instrument to cut through the background music within the overall mix.
The most important choice is the proper selection of the vocal talent and the music to be used. Most often you are going to use needledrop music from one of the many CD or online libraries. As you audition music, be mindful of what works with the voice qualities of the announcer. Think of it like the frequency ranges of an instrument. The music selected should have a frequency “hole” that is in the range of the announcer’s voice. The voice functions as an instrument, so a male announcer with a deep bass voice, is going to sound better against a track that lets his voice shine. A female voice is going to be higher pitched and often softer, so it may not work with a heavy metal track. Think of the two in tandem and don’t force a square peg into a round hole.
Soundtrack Pro, Soundbooth, GarageBand and SmartSound Sonicfire Pro are all options you may use to create your own custom score. One of the useful features in the SmartSound and Soundbooth scores is that you can adjust the intensity of arrangements to better fit under vocals. These two apps each use a different approach, but they both permit the kind of tailoring that isn’t possible with standard needledrop music.
2. Comping the VO track
It’s rare that a single read of a voice-over is going to nail the correct inflection for each and every phrase or word. The standard practice is to record multiple takes of the complete spot and also multiple takes of each sentence or phrase. As the editor, don’t settle for one overall “best” read, but edit together a composite track, so each phrase comes through with meaning. At times this will involve making edits within the word – using the front half from one take and the back half from another. Using a pro audio app instead of an NLE will help to make such edits smooth and seamless.
3. Pen tools and levels
I personally like to mix with an external fader controller, but there are times when you just have to get in with the pen tool and add specific keyframes to properly adjust levels. For instance, on a recent track, our gravely-voiced announcer read the word “dreamers”. The inflection was great, but the “ers” portion simply trailed off and was getting buried by the music. This is clearly a case, where surgical level correction is needed. Adding specific keyframes to bump up the level of “ers” versus “dream” solved the issue.
Equalizers are a good tool to affect the timbre of your talent’s voice. Basic EQs are used to accentuate or reduce the low, middle or high frequencies of the sound. Adding mids and highs can “brighten” a muddy-sounding voice. Adding lows can add some gravity to a standard male announcer. Don’t get carried away. Look through your effects toolset for an EQ that does more than the basics, by splitting the frequency ranges into more than just three bands.
The two tools used most often to control dynamics are compressors and limiters. These are often combined into a single tool. Most vocals sound better in a commercial mix with some compression, but don’t get carried away. All audio filters are “controlled distortion devices”, as a past chief engineer was fond of saying! Limiters simply stop peaks from exceeding a given level. This is referred to as “brick wall” limiting. A compressor is more appropriate for the spoken voice, but is also the trickiest to handle for the first time user.
Compressors are adjusted using three main controls: threshold, ratio and gain. Threshold is the level at which gain reduction kicks in. Ratio is the amount of reduction to be applied. A 2:1 ratio means that for every 2dB of level above the threshold setting, the compressor will give you 1dB of output above that threshold. Higher ratios mean more aggressive level reduction. As you get more aggressive, the audible output is lower, so then the gain control is used to bring up the average volume of the compressed signal. Other controls, like attack and release times and knee, determine how quickly the compressor works and how “rounded” or how “harsh” the application of the compression is. Extreme settings of all of these controls can result in the “pumping” effect that is characteristic of over-compression. That’s when the noise floor is quickly made louder in the silent spaces between the announcer’s audio.
The selective use of effects filters is the “secret sauce” to make a VO sparkling. I’ll judicially use reverb units, de-essers and exciters. Let me again emphasize subtlety. Reverb adds just a touch of “liveness” to a very dry vocal. You want to pick a reverb sound that is appropriate to the voice and the situation. The better reverb filters base their presets on room geometry, so a “church” preset will sound different than a “small hall” preset. One will have more echo than the other, based on the simulated times that it would take for audio to bounce off of a wall in a room this size.
Reverbs are pretty straightforward, but the other two may not be. De-essers are designed to reduce the sibilance in a voice. Essentially a de-esser acts as a multi-band EQ/compressor that deals with the frequency ranges of sibilant sounds, like the letter “s”. An exciter works by increasing the harmonic overtones present in all audio. Sometimes these two may be complementary and at other times they will conflict. An exciter will help to brighten the sound and add a feeling of openness, while the de-esser will reduce natural and added sibilance.
The exact mixture of EQ, compression and effects becomes the combination that will help you make a better vocal track, as well as give a signature sound to your mixes.
7. Sound design
Let’s not forget sound effects. Part of the many-GBs of data installed with Final Cut Studio are tons of sound effects. Soundbooth includes an online link to Adobe’s Resource Central. Here you can audition and download a wealth of SFX right inside the Soundbooth interface. Targeted use of sound effects for ambience or punctuation can add an interesting element to your project.
In a recent spot that I cut, all the visuals were based on the scenario of a surfer at the beach. This was filmed MOS, so the spot’s audio consisted of voice-over and music. To spruce up the mix, it was a simple matter of using the Soundtrack Pro media browser to search for beach, wave and seagull SFX – all content that’s part of the stock Final Cut Studio installation. Soundtrack Pro makes it easy to search, import and mix, all within the same interface.
Being a better editor means paying attention to sound as well as picture. The beauty of all of these software suites is that you have many more audio tools at your disposal than a decade ago. Don’t be afraid to use them!
© 2009 Oliver Peters