How Do I Record Four Channels of Audio in Camera

Sennheiser EK 6042 – Two Channel Audio Receiver

How Do I Record Four Channels of Audio in Camera?

Audio is an essential element in video production and being able to record multiple input simultaneously greatly enhances your audio recording capability.

There are various ways of doing this, including using a camera with built-in multiple audio channel inputs, and rigging up radio microphones for location filming.

The good news is that camera technology now enables high quality, four-channel audio recording, ensuring you can capture everything that is happening within the scene.

This is especially useful for self-shooting and controlling your own audio, when budgets are tight and speed is essential.

Why is Four Channel Recording Important?

With four audio channels, you have the option to use more individual inputs. Enabling you to record one or more sound sources at once, to separate tracks. You can adjust the sound balance for each of these tracks separately, to ensure you have a good balance of sound overall.

You should seek the best sound quality possible, and using multiple channels for recording helps ensure this and allows for greater flexibility in post production.

If you want to capture sound clearly on location, for example, you’ve then got a choice of channels you can edit and adjust.

Once recorded, you can mix down your four-channel recording to give you a stereo soundtrack to accompany your footage.

Built-in Four Track Audio

The Sony PXW-Z280 and PXW-FX9 come with superior professional audio capabilities. They have inbuilt four channel audio recording, and independent volume dials for precision control of external audio inputs.

Essentially, this equips these cameras with similar audio capabilities of larger equipment, while retaining exceptional portability and maneuverability.

They both feature two XLR inputs, for pro-audio devices, and a Multi-Interface (MI) shoe on the front of the top handle that integrates with Sony’s own devices, allowing two more channels.

This means you can use up to four wireless radio mic transmitters for audio input too, which is ideal for field recordings and offering you more flexibility.

What Are the Benefits of XLR Microphones?

XLR is the go-to standard for high quality audio input, and therefore is an essential component in audio recording for video.

XLR microphones send out balanced signals, which isolates noise. XLR is a superior and more robust type of connector for this type of audio set-up.

There are various quality issues you can face with audio recording, which XLR addresses, including ground loop noise, crosstalk and EMI and RFI (magnetic fields that cause interference).

Using Wireless Radio Microphones for Video

Utilizing the MI shoe on the top handle allows the use of channels three and four with Sony UWP-D11 Radio Mic single and duel receivers.

This is a very useful addition to the toolkit of the modern camera professional. It combines professional audio with an excellent level of versatility.

Advanced wireless radio microphones can now ensure that you get crisp and clean audio input, even for external shoots in demanding environmental conditions.

Fundamentally, audio is as important as the pictures you shoot, but in many situations you won’t have the luxury of being able to set up mic stands or other audio arrangements.

The quick and easy solution is to use wireless radio mics.

This means no complicated cabling, and the freedom to shoot subjects while walking and talking.

At one time, radio mics would have been seen as something of a compromise, with a limited dynamic range, prone to hiss and noise.

However, with a modern, digital mic system, like Sony’s UWP series, you can eliminate these problems.

What the UWP-D11 radio mic offers is a hybrid solution, which combines digital processing with an FM transmission.

This is a compact, rugged device with a clear and readable LCD display, backlit for reading in the dark.

The belt pack receiver has a docking port for the microphone, which makes it compatible with video cameras, such as the PXW-Z280 and FX9.

The receiver has two antennas, which in itself is not unusual, except that here they have two independent receivers. The receiver will automatically switch to the one with the best signal.

This prevents any audio dropouts occurring, usually from signal interference in buildings.

The receiver is perfect for four channel audio recording, since it can scan for any unused channel automatically. Once it has found it, the receiver will set the frequency of the transmitter to match the channel via infrared.

This advanced wireless radio mic also boasts an improved dynamic range, which is transmittable over a single FM channel. This compressed sound is then expanded to a natural range once inside the receiver.

This process is digital, which enables the mic to handle various transient sounds very well, capturing vital details in sound recording for video.

Audio Set-up for Self-shooting

Shooting a video by yourself can pose certain technical challenges, particularly when it comes to getting your audio quality right.

You don’t necessarily need a studio environment, but you should look for somewhere that offers enough quiet background.

Where you’re going to have your camera close-up, you can record directly to your camera, without an external audio recorder. You should, however, use an external microphone.  The camera’s internal microphone are normally only reserved for atmosphere or safety tracks.

With the Sony PXW-Z280 and PXW-FX9, you have individual volume dials for each of its four channel inputs, enabling you to control sound levels precisely.

The Sony PXW-FS7 also features the MI Shoe however only features two volume dials making it harder to control channels three and four on the fly. 

The Sony K1M and K2M audio input device solves this issue by offering two XLR inputs and volume dials for these channel three and four inputs.

Microphone Use

Place your external microphone as close as possible to your sound source. Under the inverse square law each time you increase your sound-to-mic distance by a factor of two, the sound pressure level reaching the mic decreases by a factor of four.

Use the fewest microphones you can to get the optimum sound recording you want. If you over-mic a shot, you can pick up too much background noise. Obviously, with four channel recording, you have the capability to add sound inputs, and in the edit decide whether the track is required or not.

Any time you’re changing your recording set-up, check your levels again, and adjust as necessary. You don’t want an audio level that’s too high or too low. Remember, some people will talk more loudly when presenting than simply talking to test audio levels.

Always monitor your sound. Missing a shot is one thing, but getting your sound levels wrong, or having a poor quality of audio, will be just as disastrous to your finished footage.