Hi Chris,
Impedance doesn’t have a lot to do with audio sensitivity. You can wangle just about any impedance by how you design the output circuitry. I’ve known some ribbon mics that come in about 50-200 ohms. They are a lot less sensitive than condenser mics.
Condenser mics are more sensitive than Dynamic mics or Ribbon mics for one simple reason. Condenser mics use floating diaphragms. Dynamic mics have diaphragms, but they have a coil of wire attached to them, so they don’t move as freely to catch the higher frequencies. Ribbon mics have a similar problem. The mass of the ribbon is much greater than that of a condenser diaphragm, so it doesn’t move to those very high frequency sounds.
Mark, are you booming or working in a studio doing voiceovers?
Regards,
Ty Ford
Cow Audio Forum Leader
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