By Sam Mallery
When one pictures a field production crew at work, it’s common to imagine a sound person in the group, hoisting a boompole over his head. One might assume that the microphone attached to the end of the boompole is a shotgun or boom microphone, but this isn’t always the case. In fact, on the set of movie productions, particularly on interior shots, shotgun microphones are rarely used. This article will introduce you to some of the alternative microphones that audio professionals commonly use on their boompoles.
Just as a carpenter has different kinds of tools in his toolbox, a sound person will also carry a number of different microphones in his sound bag. Probably the most common type of microphone used on a boompole that isn’t a shotgun microphone is a small diaphragm condenser microphone, also known as a pencil microphone. These are the same kinds of microphones that are used as drum overheads in recording and live stage use. They are regularly used for field production in controlled environments, indoors and out.
One obvious physical advantage of using a pencil microphone in the place of a shotgun microphone is that a pencil microphone is much smaller and more lightweight. This fortunate physical attribute is not the reason this type of microphone landed on the end of a boompole. It got there because in certain situations it just sounds better.
Shotgun microphones are designed to zero in on a sound from a number of feet away from the sound source. One of the byproducts of this attribute is an increased sensitivity to echoes and reflections from the surrounding walls, floor, and ceiling. These reflections create an overall unnatural sound on playback. The pick-up pattern on a small diaphragm microphone is less affected by these reflections.
Another benefit of using a small diaphragm condenser microphone in the place of a shotgun is that it has a more balanced off-axis sound. A shotgun microphone pinpoints its directionality. The operator has to be careful where the sweet spot of the shotgun is pointed.
For example, say you are operating a boompole, and the person who is speaking turns their head. Their mouth has moved away from the sweet spot of your shotgun mic. When this happens there is a fluctuation of sound quality.
A small diaphragm microphone will be more forgiving. It has a wider sweet spot, so there will be less of a sound quality change when a person turns their head while speaking. The disadvantage of using a small diaphragm condenser on a boompole is that you cannot be as far away from the subject as you can with a shotgun microphone. So either your shots need to be tighter, or the space you are recording in needs to be dead quiet. It’s a smart idea to have both kinds of microphones in your bag.
Among the more commonly used small diaphragm microphones for the working professional is the Schoeps Colette series microphone with an MK41 capsule. When using a Schoeps Colette series microphone it’s not uncommon to also have other capsules on hand such as the MK4. Another good microphone in the higher end is the Neumann KM184.
So what’s at the end of your boompole? What should be there is up to you. You’ve got to use which ever microphone sounds best in any given situation. Some professionals have been known to use other mics on their boompoles, such as large diaphragm condenser microphones, stereo shotgun microphones, etc. The job is to capture the best possible audio. What tools you use to get there are up to you. How are you supposed to know if an outdoor shot sounds better with a pencil mic or a shotgun? It’s simple. You just plug in both microphones and listen. The better sounding mic will stand out every time.
It’s a good idea to invest in some solid wind protection for your pencil microphone, should you decide to use it outdoors. A common solution for professionals using the Schoeps Colette series microphones is a Rycote Baby Ball Gag system, with a Windjammer in place if weather conditions call for one. It’s vitally important that your wind protection system fits snug with your microphone of choice.
Below we have listed some of the popular small diaphragm condenser microphones: