Selecting a Microphone

Because the microphone is the piece of gear closest to the source, it stands to reason that selecting the right tool for the job can make all the difference. There are two basic types of microphones to consider when choosing your weapon.

1) Dynamic Microphone – If you attend a live music performance, or ask a stranger to draw a microphone, a dynamic mic is most likely what you would see. The advantages of dynamic microphones are their relatively low cost, high durability, and lack of need for a power supply. The main element commonly consists of a plastic-film diaphragm connected to a coil of wire that is suspended in a permanent magnetic field. Once sound hits the diaphragm, the whole assembly moves to create a small electrical current. This inefficient design leads to a lack of high frequency detail. With quieter sources, these mics will require a lot of amplification, which can add noise to your signal.

NOTE: Dynamic mics are useful in the studio for recording sources with high SPL (Sound Pressure Level), like bass/guitar/keyboard amps and kick drums that aren’t producing a lot of high frequency detail. They are a wise choice when recording things within drumstick striking range.

Another type of dynamic microphone is called a ribbon microphone. Unlike traditional dynamic mics, these use a thin metal ribbon suspended in a magnetic field instead of a voice coil. This gives ribbon mics a smoother, more detailed sound, but adds significantly to the cost and fragility.

2) Condenser Microphone – You know that studio vocal that gives you chicken skin when you hear it, and you can almost feel the vocalist’s breath across your ear? Yeah, that was probably done with a condenser mic, whose main element consists of two small conducting plates. One is fixed, and the other is a moving diaphragm—commonly a lightweight, gold-coated plastic film. As sound hits the diaphragm causing it to vibrate, the space between the two plates changes, which varies the capacitance. When a fixed electrical charge is sent to the capacitor, these vibrations in the diaphragm can be accurately reproduced as an electrical signal. This system is much more efficient than that of dynamic microphones, resulting in a broader frequency response (near or beyond that of the human ear).