Wired vs. Wireless Mics
There are also two sub-types of microphones — wired and wireless. Wired mics are connected to the room’s sound system by a cord. Wireless mics use a radio signal to transmit your voice to the sound system. (You wear a small radio transmitter, usually on your waist.) As you might expect, they each have their own advantages,,, and problems.
The biggest problem with wired mics is the cord. It’s easy to trip on the cord, or step on it and disconnect yourself from the sound system. Your range of movement is also limited by the length of the cord.
So if you’re using a wired mic, I recommend that you walk around your presentation area before your speech and determine if there are any areas that you can’t get to because of the length of the cord. Then lay the cord loosely around the presentation area. (I don’t recommend that you coil the cord; you’re more likely to trip over the coil than on a cord that’s lying flat on the floor.)
Holding onto the cord gives you more control, but at the cost of tying up one of your hands. I generally don’t recommend it (but it can be a useful technique for short periods).
If there are any objects in your presentation area (like a table or easel), be sure not to walk around the objects without ultimately reversing your course. Otherwise, you’ll wind the cord around the object(s), resulting in a shortened cord and possibly a distracting on-stage crash.
Finally, don't play with the cord. This might seem obvious, but I've seen many speakers unnecessarily handle the mic cord (probably because of nervousness). This is distracting to your audience... so don't do it!
On the other hand, wireless mics are much easier to use —there’s no cord for you to step on or to limit your movements. Unfortunately, wireless mics have their own drawbacks:
Wireless mics are more expensive, and so are not as readily available on-site. (Many professional speakers choose to own and use their own wireless mics.)
In some cases you can encounter interference on the radio frequency that your microphone is using. At worst, you and the speaker in the next room might be using the same frequency… and your audience will hear both of you at the same time. (Many — but not all — mics allow you to change frequencies if this happens.)
You may also discover “dead zones” in your room where your wireless mic loses its signal. If you encounter these, remember to avoid them.
It’s easy to forget that you’re wearing the mic. You’ve probably seen a movie where someone goes to the bathroom while wearing a “live” mic. Granted, this is unlikely to occur (although it has happened), but the same sort of problem can occur in other ways.
A speaker I know once complained about his audience during a break — “what a bunch of stiffs”. He was safely out of the room at the time, and so out of earshot… or so he thought. But he had forgotten that his wireless lavaliere mic was turned on, and his observations were broadcast throughout the auditorium. (For some strange reason, he experienced great difficulty in establishing a rapport with his audience when break ended.)
Finally, wireless mics are usually battery powered. You don’t want to have to change batteries in the middle of your presentation, so it’s safest if you install fresh, out-of-the-pack batteries in your wireless mic before you start your presentation. (And remember to test your mic to be sure you installed the batteries correctly.)
If you recognize the potential problems that wireless mics pose and work to avoid them, wireless mics are generally preferable over their wired counterparts. However, it’s a good idea to be comfortable with using a wired mic, just in case you have no choice in using one someday.