Getting the Most from your Wireless System – Part 2
Portable wireless microphone systems are used so we can clearly understand what our subjects are saying to the camera, but did you know that the components of the same wireless systems are often used in reverse for other important production tasks? For example, they can be used to transmit your camera's audio wirelessly to a pair of headphones. You may be thinking “I don't really need to do that." But wait! Before you shrug off the idea, consider the following situations where this practice can save the day and improve the quality of your work:
- You're working with a director who wants to hear the audio as it's being recorded into the camera, but the director doesn't want to be tethered to the camera with a headphone cable. Supplying a crew member with a wireless headphone feed is a very common practice in professional settings. Having the ability to offer this to your clients will improve the level of professionalism of your services. This technique even has a fancy high-tech sounding name: IFB.
|Three essential accessories for a director:
|A director's chair, a production themed hat, and an IFB headset.
- You are shooting a wedding reception by yourself. You have a video camera on a tripod that is serving two purposes, next to the DJ booth: it's recording a fixed shot of the entire reception that you can cut away to in editing, and it's recording a clean and uninterrupted copy of the audio from the DJ's mixer for you to use in post. You are operating a second handheld camera to rove the floor and capture different moments and quotes from guests. Using the IFB method explained in this article, you'll be able to monitor your fixed camera's audio as you move around the room. This way, should anything go wrong with the fixed camera (the battery dies, a connection goes bad, etc.), you will hear it and be able to quickly remedy the situation and salvage the shoot. This method also applies to the wedding ceremony, and any other similar event or shoot.
- You're working on a shoot where the boompole operator needs to record their audio into your video camera. What is often the case in reality television and news reporting, the boompole operator and the video camera need to be able to move around independently, without being connected to one another with wires. A wireless system will be used to transmit the audio from the shotgun microphone to the audio input on your camera. The problem is that the boompole operator cannot effectively point the microphone at the right spot without being able to monitor the audio as they move around the mic. It's the equivalent to framing a shot without a viewfinder. The solution is to use a second portable wireless system in reverse as an IFB so the sound person can monitor their audio wirelessly from your camera's headphone output.
- You're doing a shoot where you need to covertly communicate with the on-screen talent, the same way that news anchors on broadcast television learn about breaking information while live on air. With the addition of an Otto earphone, the technique described in this article will enable you to rig one of these systems together using a wireless lavalier system.
What is IFB?
Considering that this practice involves surreptitious communication using tiny hidden earphones, one might assume that IFB is scrambled code for FBI. This is not the case. IFB stands for Interruptible Feedback and Interruptible Foldback, and it's used for a variety of tasks in professional broadcasting. Foldback is another term for monitoring. The only task we're concerned with in this article is remotely monitoring audio, i.e., using a wireless microphone system in reverse to transmit audio to a set of headphones. So how do you do such a thing?
How to set up an IFB system
If you're completely unfamiliar with how a wireless lavalier microphone system works, you should get to know the basics first by reading The B&H Guide to Camera Mount Wireless Microphone Systems. The focus of this article is to show you how to transform an affordable wireless microphone system into an IFB system, but it's important to note that true professionals rely on robust systems that are designed from the ground up to be IFB systems.
|Professional productions rely on dependable IFB systems like Lectrosonics.
Since we are using systems that were designed to be wireless microphones, it's not guaranteed to work as an IFB because of all the variables at play. There are lots of different headphones and lots of different wireless systems out there, and they all can have varying impedances. The impedance is the resistance in the cable that's created when two separate electronic devices are attached to each other. If the circuitry of the wireless system and the circuitry of the headphones conflict with one another, you may not be able to use it as an IFB.
Setting up an IFB system:
Step 1) Make sure you can hear sound when you plug headphones directly into the video camera. If the camera is in the wrong mode and there are no microphones active, there will be no audio for you to monitor remotely and you will not be able to tell if your IFB system is working properly.
Step 2) For remote monitoring you are going to need to attach the headphone output of your video camera into the microphone input of your wireless transmitter. This step is a potential stumbling block. Wireless transmitters will sometimes feature unusual input jacks for microphones. You're going to need a short patch cable to connect the headphone output of the video camera to the input of the wireless transmitter. Luckily for us, the headphone output jacks of video cameras are always standard 1/8" mini plugs.
If you just want to set up an IFB to communicate with on-camera talent through an earphone, you just need to wear the transmitter on your belt, and wear the lavalier microphone on your shirt so you can speak to the subject.
Step 3) Once the transmitter is attached to the headphone output of the video camera, turn on the power of the transmitter. Next, you need to plug the headphones into the output of the portable wireless receiver. There may be stumbling blocks here as well. Unfortunately, not all wireless receivers feature headphone outputs. If the wireless receiver you're using has a 1/8" output, connect your headphones or earphone to this output. If the receiver you're using features a level/volume control, start with the level turned down and gradually turn it up.
Step 4) If all of the components and impedances are agreeing with one another, you should be able to hear the audio from the video camera through the headphones just as you had when they were plugged directly into the video camera in step one.
If the system does not work as planned, experimentation is encouraged. Try adjusting the volume level of the headphone jack on the video camera. If the sound is really distorted, try turning the headphone volume on the camera down to a very low level. Also, adjusting the input level on the transmitter may help as well. If the headphones you are using don't produce any sound, try using a different pair. The impedance of a different pair of headphones may be the solution. If you are only getting sound out of one side of a pair of headphones, this is likely because there is only one channel of audio being sent by the wireless system.
The following portable wireless systems feature both 1/8" inputs on the transmitter and headphone outputs on the receiver. They're a good option for an inexpensive wireless lavalier kit that can also double as an IFB kit:
Audio Technica Pro 88W
Sony UWP systems
Sennheiser Evolution series
Thanks for checking out the B&H educational article! If you'd like to learn more about audio field production, be sure to check out these other B&H educational articles:
The B&H Guide to Portable Wireless Systems
The B&H Guide to Portable Field Mixers
The B&H Handheld Digital Audio Recorders Buyer's Guide
The B&H Guide to Boompoles
The B&H Guide to Choosing a Shotgun Microphone
How-to Minimize Wind Noise When Using a Shotgun Microphone
The B&H Guide to Choosing a Shock Mount for a Shotgun Microphone
The B&H Guide to Alternative Microphones for use on Boompoles
The B&H Guide to Lavalier Microphones
How-to Use a Plug On Transmitter with a Portable Wireless System
Setting up an IFB system is a relatively easy technique to learn, and the people you work with will really appreciate having it. If you have any more questions about IFB systems or pro audio in general, don't hesitate to contact us at 1-800-947-1181.
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