With a basic understanding of how wireless microphones work, it's time to turn our attention to some of the finer points of design. Manufacturers have many tricks up their sleeves to improve wireless microphone performance, some being more effective than others.

As already mentioned, dropouts can be a way of life regardless of the quality of your wireless system. Environments with lots of RF noise or surfaces to bounce the signal can challenge even the most expensive models. The method that the wireless receiver uses to handle dropouts is a major concern. Some systems gracefully mute the audio when the carrier drops out, with a smooth transition between the on and off states. Others create a brief "fffft!" sound as the mute circuit engages. Still other models let noise blast through at extremely loud levels. This burst-of-noise approach is clearly the least desirable. A wireless system's ability to handle dropouts often improves with price, though not in every case. The best way to learn a system's characteristics is to test it out yourself.

Many wireless microphone manufacturers use "companding" noise reduction. This system is so named because it combines a COMPression process at the transmitter with an expANDING step at the receiver. Companding noise reduction doesn't help with dropout noise. Instead, it reduces the low-level hiss that all wireless systems add to the audio. Companding noise reduction can make a significant improvement in the cleanliness of the signal, delivering sound almost on-par with a wired microphone. UHF wireless systems with noise reduction offer the best possible sound, often indistinguishable from that of a wired system.

Remember that the heart of a wireless microphone system is the microphone itself. All the nifty electronics, noise reduction and antenna arrays won't make a bad microphone sound better. Poorly designed mikes will often sound dark and dull or thin and tinny. If you're unhappy with the sound of a given wireless system, the problem could be in the microphone itself. Try another wireless microphone at the same price point to see if your sound improves.

Don't get too wrapped up in maximum range figures as printed by manufacturers. Those figures are often inflated, and represent absolute best-case performance. With so many variables affecting a wireless microphone's signal, it's possible that a mike rated at just 150 feet could outperform one rated at 800 feet in the same conditions. Shoot in a different locale, and the latter microphone may soundly outperform the one with a shorter range spec.

Finally, there are a lot of tricks you can use to improve the audio from any wireless system--see "Wireless Wisdom" sidebar for more details. With your new-found knowledge of wireless mikes, you can venture fearlessly into your next video production...with no wires attached.