A Guide to Audio for Filming

Sound on! Everything about audio

If you speak a lot in your videos, you naturally need to be clearly understandable! The quality of the audio is almost as important as the quality of the video. Ideally, the viewers of your videos hear clear sound without noise and ambient sound. But how do you achieve this? With a good microphone, of course!

Almost every camera that can film also records sound. However, the camera's internal microphone is generally not the best choice for recording directed sound — it picks up everything in front of and around the camera, including sounds you do not want. In this article about audio we explain which types of microphones exist and which are best for your videos.

How does a microphone work?

Before we show which microphones are suitable, let us first look at how microphones work. Each type picks up sound in a different way, so for every situation there is a different suitable microphone. Below the most important types are explained.

Omnidirectional

An omnidirectional microphone picks up all sound around it, from all sides simultaneously. Ideal if you want to capture ambient sound and when sound can come from all directions. Omnidirectional microphones are often used for interviews and presentations. For vlogging and filming they are less suitable.

Bidirectional

A bidirectional microphone records sound from the front and back simultaneously. Sound from the sides is not recorded. Ideal as a single central microphone placed between two people when recording a conversation or interview — often used in podcast or radio studios.

Lobar or unidirectional

Lobar or unidirectional microphones are perfect for directed sound and are also called shotgun microphones. You record sound from in front of the microphone and minimally from the sides. The directional microphone is widely used on professional film sets, but is difficult to work with and is intended for professional sound engineers.

Cardioid

Cardioid microphones mainly record sound from the front but with a fairly wide range. The most common type of microphone, used for interviews, singers, musical instruments and performances. If you don't mind some ambient sound, the cardioid is a good choice for video recordings.

Supercardioid

The supercardioid microphone is the most popular type among filmmakers and vloggers. Like the lobar microphone, you can record very directed sound, but thanks to a wider pickup pattern there is a bit more room for error. Often referred to as a 'shotgun' or 'videomic'. Many of these connect directly to a camera, so you record the sound wherever you point the camera — no separate microphone needed. Ideal!

Hypercardioid

Hypercardioid microphones sit between the regular cardioid and supercardioid. You pick up slightly more ambient sound, but can still direct to some extent. Often used for recording musical instruments.

Which type of microphone?

Now that you know which recording patterns exist, we can look at which type of microphone is most suitable for you. The microphone you ultimately choose depends on the type of videos you make!

The shotgun or videomic

The shotgun or videomic is placed directly on your camera. They fit most video, DSLR and mirrorless cameras and connect with a 3.5mm jack cable. The recording pattern is supercardioid, so you can direct it well. While filming, point the camera (and the attached microphone) at the source of the sound you want to record — you film and record directed audio at the same time. Below we have selected three enormously popular videomics, each fitting a different budget. The Rode Videomic NTG is a perfect microphone for the advanced filmmaker and combines the best of a shotgun and lobar microphone.

The lavalier

Lavalier microphones are those small, almost invisible microphones that TV presenters often wear. Lavaliers are often wireless and can easily be attached to clothing. In films they are frequently hidden just under the collar of an actor. Thanks to the omnidirectional recording pattern, voice audio can be recorded well. If you don't mind the microphone being visible, or you don't want a large microphone on your camera, the lavalier is perfect for your videos. Do bear in mind that you record virtually no ambient sound with a lavalier.

Accessories

Having just the microphone on your camera is usually not enough for perfect sound quality. If you often record videos outdoors, you will probably have experienced problems with wind noise. Many microphones come with a foam windshield that already prevents a lot of noise, but in strong wind this is not sufficient. For this there are so-called deadcats — essentially very furry windshields for your microphone. The hairs filter out the wind so you can enjoy beautiful audio recordings.

The microphones above all have a 3.5mm jack connection that fits most cameras. More professional microphones often have an XLR connection with three pins, fitting professional cameras or external audio recorders.

Fortunately there are also adapters that create a transition from XLR to 3.5mm, so you can also use these microphones on your DSLR or mirrorless camera. Not every XLR microphone is compatible — some draw power from the camera, which often does not work in combination with a 3.5mm adapter.

Tips from an audio specialist

• It is very important to have the microphone as close to your subject as possible. The less space between the microphone and the subject, the less ambient sound you pick up. That is why lavalier microphones are enormously popular among vloggers.
• Many people make the mistake of thinking that Stereo is always better than Mono, while both types have their own function. Mono is better for vlogging, while Stereo is better for musicians.
• Make sure you have a windshield when filming outdoors. For every microphone, Rode offers a deadcat. This furry friend ensures that your recordings are not overwhelmed by wind noise.