Audio Advice: Traveling Sounds

Hal Robertson
July 2005

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You know the game: name five things you would take if stranded on a desert island. Now, before you name a cell phone, matches, and a case of your favorite beverage, let's twist the game a bit and decide on five audio tools that no video editor can be without, whether you're stranded on a desert island or a Dallas airport. The premise may sound a bit silly, but think about it. You won't always edit in your nice, cushy edit suite. In fact, one day you may find yourself frantically slashing video on an airplane or in the back seat of a car. You won't have all your fancy plug-ins or decent speakers to monitor your audio with. Should you find yourself in such a situation, you'll be glad you mastered these five essential tools.

Probably the most important audio tool in your kit, normalizing analyzes the audio in a video clip and boosts the volume so the peaks are at maximum volume. This indispensable process ensures all your audio clips will play back at their full potential. Every video platform is different, but the procedure usually involves selecting the clip, and then choosing the Normalize option. Unless your original audio was pretty loud during recording, the Normalize process will apply some boost -- sometimes quite a bit -- resulting in a nice, loud clip that can compete with other audio elements in your project. Tip: when normalizing interview audio, import longer clips and apply normalization to the entire clip before slicing it into smaller chunks. Since the normalization will stay with each edit, you can do it once instead of dozens of times. Regardless of the audio you're normalizing, you may have to manually tweak the settings to get things just right.

Your car uses several filters to keep bad things out of the engine. Your audio can benefit from some filtering too. Audio filters allow certain parts of the sound spectrum to pass while removing other parts. Your very best filter friend is the high-pass filter. Applying a high-pass filter to your recorded audio removes the low-frequency elements -- like wind and handling noise -- and lets the upper portion through unaffected. A low-pass filter removes the higher frequencies while a band pass filter removes some of the upper and lower audio, resulting in a narrow audio spectrum. Applying a filter is usually a drag-and-drop affair, selecting the filter from a list and dragging it onto the appropriate audio clip. Afterward, you'll have to make some adjustments to the filter since the default settings rarely work for utility use. Filter setup involves adjusting the cutoff frequency for your intended use. For example, a high-pass filter on your dialog track might have a cutoff frequency of 100Hz. This ensures a minimum of low frequency nasties will make it into your video.

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