Microphones Flashcards
What is a microphone?
A transducer that converts sound energy into electrical energy.
What does a dynamic microphone feature?
Diaphragm, voice coil and a magnet.
How does a dynamic microphone record sound?
Voice coil surrounded by magnetic field, attached to rear of diaphragm. Motion of voice coil generates electrical signal corresponding to picked up sound
What are the benefits of a dynamic microphone’s simple construction?
Economical, rugged.
Handles high SPL.
Unaffected by extreme temperatures or humidity.
What are the disadvantages of a dynamic microphone’s construction?
Slow transient response (introducing form of acoustic compression).
Doesn’t have a flat frequency response.
Limited high frequency response.
What are live situations referred to as?
Reinforcement.
How does a condenser microphone work?
Diaphragm electrically charged with a backplate, forming a sound-sensitive capacitor. Changing space between diaphragm and backplate changes capacity of capacitor. This variation is spacing produces the electric signal.
How is a condenser microphone charged?
Phantom power (48V). Battery powered.
What are the three possible switches found on a condenser microphone?
Pick up pattern: different combinations of capsules (polar pattern)
Low-cut: eliminates low frequency rumble therefore proximity effect
Pad switch: -10dB
What are the advantages of a condenser microphone?
Fast transient response.
Flat frequency response.
Wide dynamic and frequency range.
Good signal to noise ratio.
Where are electret microphones commonly found?
Computers, phones
What is a PZM microphone? What does it stand for?
Piezoelectric.
Surface microphone which is a mini condenser mounted near a reflective surface (found on electro acoustic guitars)
What is the proximity effect? What is the benefit of having it?
Scalic effect of a low end boost if unidirectional microphone is placed too close to sound source.
It can add warmth.
What does an omnidirectional microphone do? Give one advantage and one disadvantage.
Picks up from all directions.
No proximity effect / ambient recording.
Feedback unavoidable in reinforcement
How does a cardioid microphone work? When would this polar pattern be used?
Rejects noise at back of microphone.
Avoids spill for close micing, rejects room ambience.