When producing a video, some would argue that good audio is more important than the visual component. Nothing screams amateur like poor quality audio. It is distracting to the viewer and in some cases makes it impossible for them to understand what is being said. In either case, they are likely to just stop watching and move on.
Here are some simple ways to achieve good audio for your next project.
Capturing Clean Audio:
Good audio depends mostly on the recording process. If you mess up this part, there’s often no recovering. So be sure to do everything you can to capture clean audio on the day of filming.
1. Choose your location carefully. Your shoot should be set up in a quiet space with little to no background noise. Turn off the air conditioning, unplug a refrigerator, kindly ask others nearby to take their conversations elsewhere. Outdoor interviews are often difficult because even if you’re not in a flight path or on a noisy city street, there is still likely to be the occasional dog barking or trash truck in the background that could ruin that part of the interview.
2. Use an external microphone. There is practically no way to get good audio for a video with just the microphone on your camera. The single most important rule when it comes good sound is the proximity of the mic to the sound source. The microphone needs to be near the mouth of the person speaking (preferably 3 to 12 inches away). If this is the only change you make to your audio recording process, you will see a dramatic improvement! So get a mic!
3. Recording levels are important. A lot of video recording equipment automatically adjusts the recording level based on the loudness of the environment. That works, but it also means that your volume in the recording will be constantly changing, which can be distracting and there is no easy way to undo that. If you’re able to set recording levels manually, that will be better, with one caveat — they must be set correctly! Set the levels as high as you can without the audio clipping or distorting. There will be meters on your recording equipment, so just remember that you never want the meters to hit the top (the red) because there’s no recovering that distorted portion of the recording. You also don’t want the levels too soft. If in the editing process you have to turn the volume up excessively to make up for low recording levels, it will introduce noise or hissing that’s difficult to get rid of.
Equipment:
There are two types of microphones that work best for video:
1. A lavalier microphone is the tiny one that clips onto people’s shirts. It can be handy because it stays close to the mouth, and being wireless makes it great for situations when the speaker is walking around. Lavalier microphones don’t offer much wind protection so if you’re outside, you might encounter a low rumble from wind noise. Lavaliers can also be visually distracting. They are usually seen clipped to outside of the speaker’s clothing, and it can be tricky to hide them without introducing rustling noise from clothing. A lavalier mic would generally be the best choice when the person who is speaking is on the move. Today there are many affordable wireless lav options, costing a few hundred dollars. You can just plug them into your camera and there are even adaptors to plug them directly into your phone, in case you’re using that as your camera.
2. A shotgun microphone (or boom mic) is typically attached to the end of a boom pole. The pole is either mounted on a stand or held by someone who is also monitoring the audio and adjusting the levels. Shotgun microphones are excellent at picking up a narrow pattern of sound directly in front of them and are great for sit-down interviews. You can position the mic above the person’s head, just outside the frame. This way the mic is close to the subject without being visible in your shot. These microphones generally produce higher quality audio than a lavalier would and can work well outside because you can put a large windscreen over them to block out wind noise. The biggest downside to the boom mic is that it can be difficult to get the mic close enough to the person talking — especially on wide angle shots or walking shots.
Post Production:
After you’ve recorded the audio, you will often want to make some adjustments in post-production.
1. Depending on your editing software, there is usually a feature to normalize the audio. This means that the software will adjust the volume to the point where it’s as loud as possible without clipping or distorting. You want your audio volume to be near the top of your meters in order for it to play back at the proper volume when people watch it. If your editing software does not offer audio normalizing, you can do it yourself by turning up the volume until the waveforms have reached the top.
2. Applying a compressor / limier can be very helpful, especially for dialogue. Compression in essence evens out the volume, which can be helpful for times when someone laughs loudly or raises their voice. A limiter prevents levels from distorting by setting a ceiling and not allowing any part of the recording to exceed that set ceiling. A compressor and limiter both help you smooth out the volume of your dialogue and allow you to raise the overall volume, making your audio more pleasing to listen to.
3. In some cases you may want to employ an equalizer, but be careful. You could easily do more harm than good with EQ. This is a skill that takes considerable practice, expertise, and a finely tuned ear.
4. If your editing software offers audio noise reduction, this can be a very valuable tool for some situations (mostly when one of the important parts of capturing clean audio outlined above was not well executed.)
By following these simple tips, you can greatly improve the quality of your audio, and thus your entire video project. Go ahead — try them out, and hear the difference!
