Earlier we mentioned that condenser microphones require power. Depending on the make and model, that power can come from something as simple as an AA battery. In fact, many shotgun microphones use this as a power source, which is handy for cameras without power options.

Phantom power is the industry standard for condenser microphones and comes from balanced input jacks on mixers and cameras. A little switch supplies the mic with 48 volts, but there's no risk of shock. Although the voltage is fairly high, there's not enough current to give you even a tingle.

There's only so much volume a microphone can take. Don't worry: it won't blow up, but it can sound pretty bad. Several factors determine the maximum volume level - the diaphragm and electronics are at the top of the list. Years ago, a loud blast could permanently damage a ribbon or condenser microphone. Today's models are much more durable. The maximum SPL number simply indicates the loudest sound the mic can reproduce cleanly. Anything above that risks distortion.

There's no mystery to this information, but it's important anyway. Consider how you will use the microphone and the impact of size and weight in your production. For instance, when you are choosing a shotgun mic, the length can be critical if you mount it to the camera. While a longer microphone may provide more audio focus, you also run the risk of a drooping mic in the top of your frame. Using a zeppelin and/or furry windsock amplifies this potential. With lapel mics, smaller is usually better, but only when balanced against sound quality.

Some manufacturers are a bit skimpy when it comes to accessories. While most microphones come with some sort of mounting clip, it may not be the one you want or need. This can contribute significantly to the purchase price. Look closely for windscreens, shock mounts or adapters that may be necessary for your setup.

Everything you need is out there somewhere - maybe in a bundled package. Just don't assume it's included unless you see it written in the literature.

It's easy to get buried in the details when shopping for a microphone. The final decision is a delicate balance of price, performance, sound quality and suitability. There is no perfect microphone, and the right one for your production may be completely wrong for my style. The good news is that high-quality microphones are available at virtually every price point today. Now that you know how to read the spec sheets, there's nothing to stop you finding that magic balance of price and quality.

Contributing Editor Hal Robertson is a digital media producer and technology consultant.

Several items just don't translate to a spec sheet - the way a given microphone fits in your hand or works with your equipment, for example. Another item is handling noise. While some mics are deathly silent when handled, others rattle and bang like there's something loose inside. Finally, there is the sound. Regardless of how good the mic looks on paper, the sound seals the deal. The temptation is to find the lowest price and order online. But, whenever possible, audition potential microphones with your own gear. This way, you'll find the perfect fit and minimize surprises.