10 Tips for Better Audio in Digital Video Production
Today's digital recording equipment is more accurate than ever at capturing audio with vivid and crisp detail, however, videographers quickly discover that it's usually the distracting noises that get captured the most vividly and crisply. There are many steps that can be taken before a shoot that will help prevent these audio problems from occurring, and lots of measures taken in post production to repair the damage that may already have been done. Not making this extra effort can mean the difference between a merely adequate product and a more polished and professional piece.
Part One - Pre-production - Take a few moments to eliminate problems before they occur
Tip 1) Make sure you have the right mic for the job
Having the right microphone positioned in the right spot makes all the difference in the world to the quality of your audio. The microphones that are commonly used in video production come in a variety of shapes and sizes, and each of these tools has a unique strength that allow them to capture better audio in a given situation. We strongly consider investing in at least one auxiliary microphone for your camera setup!
Stereo Microphones- With the proper gain adjustment, these mics can capture natural sounding musical performances and ambiances both loud and quiet.
Tip 2) Choose your shooting locations carefully to avoid problematic audio environments
Remember to always scope out your shooting locations in advance when possible. Try to bring the camera and microphone that you'll be shooting with and a good pair of headphones to identify problem noise sources. What you hear through the microphone is often very different than what you can hear with just your ears. That air conditioner noise that you have subconsciously blocked out may seem much louder when listening through your headphones.
Tip 3) When microphones are used outdoors they require wind protection
If you are going to be out in the elements, make sure that you have adequate wind and weather protection for you microphones. Keep in mind that lightweight foam windscreens will not be adequate for any type of real breeze, so you should consider heavier wind and rain protection to insure better results when shooting outside. Lower frequency wind noise and dripping rain can easily render your work unusable. Learn all about wind protection for shotgun microphones here.
The Tascam HD-P2 features XLR inputs and can sync to a time code clock
Tip 4) Consider capturing audio using a separate recorder
Some smaller DV cameras employ an automatic gain circuit that maintains consistent input recording levels so that you don't have to. The problem with this system is that it does not always yield desirable results and in some cameras it cannot be bypassed. Making use of a separate audio recorder will not only avoid this problem by giving you more control over levels, but you will gain superior results from a dedicated high quality audio recorder. Learn how to integrate a portable digital audio recorder into a video camera set-up in this B&H educational article. For a breakdown of smaller handheld recorders check out this B&H Buyer's Guide.
Tip 5) Use hardware compressors and limiters when taping in the studio
A studio interview or voiceover situation is a great time to make use of a hardware dynamics processor. Compressors and limiters are often overlooked units that can help smooth out your signal and allow you to get more level to your recorder. Many portable field mixers have built in limiters so don't be afraid to try them out in your studio as well- a little limiting can work wonders.
Post-production - We all make mistakes, now here's how can to fix them.
Tip 6) Consider using a dedicated audio software in addition to your video editing software
If you wish you had more audio editing power than your video editing software can provide, you might consider working with a dedicated audio application. Most video editing software is focused mainly on video. Highly specialized programs like Peak Pro (for Apple computers) and Sound Forge (for Windows) will empower you with many more editing options for audio. If you want to go beyond just using two tracks of audio in your projects you should consider a multi-track application like Pro Tools, Digital Performer, or Vegas Pro.
Bias Peak LE 6 is an inexpensive post production audio editor for Mac
Tip 7) Apply restoration
What can you do if background noise from an air conditioner has ruined an otherwise well recorded interview? Restoration software can operate within your host editing program as a plug-in, or as a standalone application. It can help you reduce problematic audio situations like background noise, clicks, pops, crackles, and wind noise. 60 cycle hum (a term that audio professionals use to refer to that nasty humming sound that electronics sometimes produce), low frequency rumble, and switching noise all fall under the category of undesirable sounds that restoration software can improve. There are many options out there, from the streamlined Soundsoap to the more involved Waves Restoration Bundle, each offering different levels of power, detail, and versatility.
Tip 8) Become more proficient at making smooth edits in your audio software
As with video, smooth audio edits should be virtually unnoticeable when executed properly. With a little practice, you should be able to remove unwanted coughs and other extraneous sounds when they do not support your video footage. It is well worth your while spending some extra time learning to properly trim your audio segments by making use of all your available software options. Trimming at "zero crossing" and making use of your software's crossfading tools, for example, will help prevent audible clicks and pops from occurring between transitions.
Ableton Live offers some unique tools in audio post for video
Tip 9) Become more familiar with EQ and mixing concepts
Effectively mixing several audio tracks is a little more complex than merely adjusting volume levels and transitions between them. Each element in your project will sit in a different frequency range and should be equalized accordingly to preserve its own sonic space when combined with other elements. Dialogue, for example, carries little low frequency content and can therefore be "rolled-off" to prevent low frequency buildup against other tracks. This prevents unfavorable interaction with other low frequency content such as your musical elements. Proper EQ can make voices stand out, minimize extraneous rumblings, and tame an overly bright sounding segment, amongst other things. If you're in this for the long-run, spend a little time researching and becoming more familiar with the concepts of the audio frequency spectrum and equalization.
Tip 10) Consider employing some secret weapons!
Some equipment just defies conventional description. There are certain tools that just make your audio sound better, even if you're not really sure what they're doing. Consider this category the "push-this-button-to-make-it-sound-good" tools. Two such products are the BBE Sonic Maximizer and the Aphex Aural Exciter. They do their thing with surprisingly few controls, so they're easy to get a handle on. By compensating for phase and amplitude distortions before your signal arrives at the speaker, the Sonic Maximizer delivers added definition and a natural clarity to your overall mix or to individual tracks. It is surprisingly effective and is available as both hardware and software.
For those just beginning to focus on better audio in their video work, we hope that these ten tips introduce you to some new concepts that you may not have come across on your own. If you are a seasoned veteran, perhaps some of these points will act as a reminder of concepts you may have overlooked, and may be worth revisiting. If you have any more questions about improving your audio in your video productions, please tell us!