Microphone Buying Guide

Condenser and dynamic microphones

All microphones are not the same, and not all mics are good at all things. Some microphones are better for vocals and some are better for instruments. Basically, you need a microphone that will capture as much of the range of a sound source as possible. If you’re shopping for home use, be aware that you need a lot less range than you would in a professional recording studio, as most compressed audio and video formats devour some of the audio range, negating the quality of high-end microphones.

Condenser microphones are the best available. This design uses the motion of a diaphragm against a metal backplate to translate sound into electrical frequencies. Condenser microphones are expensive and extremely fragile, and these microphones require what’s known as “phantom power,” or electricity from a mixing board or preamp. For studio use, a condenser microphone is the best choice. If you’re plugging straight into a PC, a condenser mic won’t work.

Dynamic microphones don’t need additional power and can plug straight into your PC or a mixing board. These microphones are more durable and less expensive than condenser mics, but they don’t capture the same range of sound. Dynamic microphones are much more forgiving of loud noises and rough handling, making them the best choice for home use, nightclubs and traveling musicians. Most dynamic mics use a moving coil in a magnetic field to capture sound; “ribbon” microphones are a subtype of dynamic mics that use a thin metal ribbon instead of a coil.

Microphone patterns

The recording range of a microphone is its Polar Pattern. This tells you where the mic can be placed relative to a sound source, such as your voice or a guitar, and pick up the most signal.

There are two broad categories of microphone polar patterns: directional and cardioid. Directional microphones are further categorized as omindirectional, which picks up sounds in a 360º pattern; half-omindirectional (or bidirectional), which gathers sound in a 180º pattern in front of the mic, and bi-directional, which picks up sound to about 110º to the front and rear of the mic but rejects sounds from the sides.

Cardiod microphone patterns are heart-shaped, with the strongest pickup to the front and front sides of the microphone. Supercardioid and Hypercardiod offer a little more sensitivity directly behind the mic.

Choosing the right pattern depends on how you’ll use the microphone. Cardioid patterns are best for vocals and voice in most home and live performance settings. If you’re micing a guitar or brass instrument, use a supercardioid or hypercardiod microphone that cuts down on vibrations.

Directional microphones pick up a lot of ambient room noise and aren’t good at isolating individual sound sources unless they’re placed very close. Omnidirectional mics are good for drums and organs, and their lower sensitivity to vocal pops (from breathing and “p” sounds”) can be useful in a home or studio setting that doesn’t have a lot of echo. Bidirectional microphones are best for one-on-one interviews or live vocals where space is at a premium.

Taking pattern and microphone type into account, the best choice for general vocal and instrument use is a dynamic cardioid microphone. Condenser mics should be reserved for professional use and the most well-equipped home studios, where you want to capture a full range of sound levels from quiet to loud.

Cables, stands and mounts

Most microphones connect with a standard, three-prong XLR cable. You can find specialized cords that have a 1/8” microphone jack on one end, which is standard for most computers, or a ½” phono jack common on amplifiers. You can also get separate adaptors. Don’t get more cord than you need. Longer cords lose some of the signal as it travels from the microphone to the mixing board, amplifier or input jack.

Even if you plan to hold a microphone in your hand while you use it, you should have a microphone stand for storage. Microphones shouldn’t be left sitting on a desk where they’re subject to falls and spills. Most microphones come with a standard mount that screws onto a stand. A simple desktop stand will do for home use, just make sure it doesn’t transfer vibrations to the microphone.

Sensitive condenser microphones need specialized mounts that isolate their diaphragms from vibration. These microphones are typically suspended in a square frame with elastics, and the frame can be hung from a wall or ceiling. Desk mounts have an adjustable arm similar to those found on desk lamps. The important thing with condenser microphones is to make sure that no vibrations get to the mic, as they will get sent to the amplifier.

Microphone extras

Most handheld microphones are available with or without an on/off switch. The rule of thumb is to avoid microphones with a switch if you’ll be using them with a mixing board. The switch can be handy for home use.

Pop filters and windscreens eliminate breathing noise and wind sounds. Membrane pop filters are the best choice for home and studio use. Choose a foam windscreen for live performances, but make sure the foam isn’t so thick that it muffles sound.

Wireless microphone kits are also available. The cost of these microphones makes them practical only for live performance venues like theaters and nightclubs. You may want to think twice about investing in wireless microphones, however, because the radio frequencies they use could be reallocated in 2009.

Need to know more?

• Microphone Mysteries Revealed
  http://www.sweetwater.com/insync/techtip.php?find=07/29/2003
• Proper Podcast Microphone Placement
  http://www.podcastconsultant.net/2007/01/13/proper-microphone-placement/
• How to Build a Home Recording Studio for Less Than $1,000
  http://www.linux.com/articles/39751