Microphone Transducers

A dynamic microphone works like a tiny loudspeaker in reverse: sound moves a diaphragm attached to a coil, and the coil moving through a magnetic field generates a voltage. Because the mechanism is simple and rugged, dynamics need no power, tolerate heat and rough handling, and take enormous sound pressure — well over 140 dB SPL. That is exactly why they live on snare drums, guitar cabinets, and loud vocals.

A condenser microphone is more delicate and more detailed. It senses a charged diaphragm moving against a fixed backplate, and it needs phantom power both to hold that charge and to run a small internal preamp. The reward is far greater sensitivity, a faster response to transients, and extended high-frequency detail. The catch is that it hears everything — room, spill, and handling noise included — so it asks more of your placement.

A ribbon microphone suspends a thin corrugated foil between magnets. It gives a smooth, natural top end and naturally picks up in a figure-8 pattern, hearing front and back while rejecting the sides. Ribbons are fragile and dislike sudden blasts of air, and many older models can be ruined by phantom power, so confirm before you patch one. One number ties all three together: sensitivity, measured in millivolts per pascal. A condenser might deliver 20 mV/Pa where a dynamic gives 2 mV/Pa — a tenfold difference you will feel immediately when you set the preamp gain.

Beyond the three families, the intended job narrows the field further. A studio microphone favours detail and a low noise floor; a live microphone, ruggedness and feedback rejection; a measurement microphone, a flat, calibrated response for tuning a system; a lavalier, discretion; an ENG shotgun, reach and endurance outdoors. The same transducer type turns up in several of those roles, so the job rarely picks the microphone for you — it just tells you which compromises you are allowed to make.