Questions Before Buying

This leads us to the three questions you need to ask before buying a microphone. Note that you have to ask the same questions whether the microphone is wired or wireless, since the same issues arise with each.

1. What is the Pickup Pattern?

The pickup pattern, or directionality, of the microphone defines which sounds the microphone picks up and which ones it ignores. At one extreme are the "omnidirectional" microphones built into your camcorder that pick up sound equally from all sides of the camcorder. At the other extreme are "unidirectional" microphones that pick up sound from a single direction, and shut out all other noises.

For some microphones, like the shotguns we've been discussing, the pickup pattern is obvious. Shotgun microphones are designed to ignore ambient sound, and are extremely one-directional. In specification sheets for shotgun microphones, you'll frequently see terms like cardioid, super-cardioid, or even hyper-cardioid pickup patterns, which designate increasingly greater exclusions of ambient sound to focus more completely on the sound directly in front of the microphone.

Most other microphones come in either omnidirectional or cardioid patterns, and you need to be careful to get the right microphone for the intended use. For example, if you're buying a boundary microphone for use on a lectern where you want just the speaker's voice picked up, choose a cardioid pattern. However, if you're buying a boundary microphone for a conference room where all participants must be heard, an omnidirectional microphone is a better option.

It's also critical to know the pickup pattern when using the microphone. For example, if you're using a hyper-cardioid shotgun microphone to pick up a group discussion, you probably won't capture the panelists at the periphery of the group. Similarly, a handheld microphone with a cardioid pattern will eliminate sounds not emanating from directly in front of the top of the microphone.

2. Should I go Powered or Unpowered?

The next essential fact is whether the microphone requires power or not. As we discussed previously, if the microphone requires power, and your camcorder's microphone doesn't offer plug-in power, you'll have to figure out another way to power the microphone.

Most microphones that need power simply list "Phantom Power Requirements" or something similar on the specification sheet. All condenser-type microphones need power, either from the camcorder or battery. In contrast, dynamic microphones do not need power and can run even if your camcorder doesn't offer plug-in power assuming your camera gives you some way to connect it, of course. Which leads to our next essential consideration: connector type.

3. What's the Connector Type?

Virtually all professional microphones connect via an XLRM connector, which is shorthand for XLR male. This means that the three XLR pins are sticking out of the connector and that your cable will need a corresponding female connector to attach to the microphone. Birds and bees at eleven.

XLR is a favored technology because it is "balanced," which means cables can run long distances without picking up noise from electrical wires and other sources. In contrast, unbalanced cables, such as those typically terminated with 3.5mm jacks, pick up noise easily, especially as cable lengths grow.

For this reason, you'll rarely see microphones that connect via 3.5mm plug apart from the shotgun microphones that mount directly on your camcordes. The other primary exceptions are wireless microphones such as the Sony WCS-999 shown in Figure 2.3, which uses a 3.5mm jack to connect to your camcorder. However, since the receiver mounts on your camcorder, the distance traveled over the unbalanced wiring is relatively short.