Audio is one of the most frequently over looked, but one of the most important parts of a video for YouTube. Almost anybody can post a video online now but one thing that will help that video stand alone in the crowd is high quality audio. When squaring audio there are 3 main things to consider; audio source, audio levels and ambient noise.
The most important thing to consider when recording audio for video is the audio source. Be it a built in microphone, an external microphone or a feed from a mixer the source will be the biggest determining factor of audio quality.
Almost every video camera has a built in microphone, and almost every built in microphone will produce sub-par audio. The audio from a built in microphone will often pick up the noise from the camera itself, the noise made by operating the camera and not to mention they are not usually very direction so they pick up a lot of ambient noise.
If there is no other option but to use the built in microphone the best solution is to get close to what ever audio is being recorded. If it is a person speaking, zoom out and move the camera closer to the person. If it is the sound of a saw cutting, again zoom out and move it. The closer the microphone is the better the audio will be.
An external microphone will almost always give better audio quality than a built in microphone. Many video cameras will have an external audio jack that will either be a stereo mini jack or XLR plugs on high-end cameras. Almost all microphones will work with any camera that has a microphone jack, either directly or with the use of adapters.
When interviewing a person, or having a person speak to camera a lav microphone will help eliminate unwanted noise by putting the microphone very close to the persons mouth. This is how all TV News and Sports anchors audio is captured.
When working in noisy areas or performing on the street interviews a stick mic will often be the best choice. Stick mics are what you will often see on-sceen reporters using with a mic flag that shows what station they work for. This type of microphone is good at eliminating unwanted noises and is easy for a person to point back and forth from themselves to another person.
In high end productions a boom mic is often used. The boom mic requires an operator and can be complicated. But in skilled hands it will acquire the best possible sound. They are highly directional and very sensitive. A good boom operator can acquire sound from multiple people and other sources at the same time.
Audio levels are just as important as the audio source. If there is a great audio source but the level is being over driven the audio will be unusable. Many cameras that have an external audio jack will allow the operator to control the levels of the audio. If the camera does not have controls, it will have automatically adjust the levels for the operator.
When using a camera with manual controls, it is always better to set the levels than to let the camera do it automatically. When a camera sets the levels automatically it will adjust the audio level to the loudest sound.
Many times, between sentences of a speaker there will be a pause. During this pause the camera will then adjust to the loudest sound, which could be something like the air conditioner, which is pretty quiet. When the speaker starts to talk again the first work will be very loud and then the camera will adjust again.
When setting the levels manually it is best to have the peak of the meters at about the mid range. That will assure that the audio will be clear and if the source gets louder it will not distort. If the camera has decibel (db) meters, on a digital camera set the peak at -20db and on an analog camera set it at 0db.
Ambient noise is often the biggest problem for audio. Ambient can range from a loud bird chirping to a plane flying overhead to a loud street. Avoiding ambient noise is always the best idea, but if not possible there are a few things that can be done to help reduce it.
When in a noisy area try to always use an external mic. In very noisy areas a stick mic is the best option, but if the look of a stick mic is not welcome a lav will work fine. If an external mic is not an option always face the camera mic away from the noise source.
Here are a few tricks to help avoid ambient noise.
- Use natural barriers, such as houses, trees, walls and cars to block noises,
- Use the body of the person speaking to block noise (turn their back to the noise when using a lav or stick mic)
- Get the microphone closer to the source of audio
- Unplug noisy appliances
Now get out there and make a video with outstanding audio, your viewers will thank you!
Thanks to Aranda for giving me the permission to use their awesome music: Music: Aranda – Whyyawannabringmedown www.facebook.com www.myspace.com www.twitter.com Im not really satisfied with the outcome, just because i lost a bit motivation at the end, but i still think its pretty good and deserves a favourite 
