Microphones

Question 1

purpose of mics

Answer 1

to convert acoustic vibrations (in the form of air pressure) to
electrical energy so it can be amplified or recorded

Question 2

major parts of a mic

Answer 2

DIAPHRAGM, transducer, casing

Question 3

how does a dynamic mic work?

Answer 3

A dynamic microphone operates like a speaker in reverse. The diaphragm is moved by changing sound pressure. This moves the coil, which causes current to flow as lines of flux from the magnet are cut. So, instead of putting electrical energy into the coil (as in a speaker) you get energy out of it.

Question 4

advantages of dynamic mics

Answer 4

Robust and durable, can be relatively inexpensive, insensitive to changes in humidity, needs no external or internal power to operate, can be made fairly small.

Question 5

disadvantages of dynamic mics

Answer 5

Resonant peak in the frequency response

Question 6

advantages of ribbon mics

Answer 6

Relatively flat frequency response, extended high-frequency response as compared to dynamics, needs no external or internal power to operate.

Question 7

disadvantages of ribbon mics

Answer 7

Fragile

Question 8

how do ribbon mics work?

Answer 8

• ribbon mics work by reacting to the change in air velocity
• a light metal ribbon is suspended between the poles of a magnet. When the ribbon vibrates, it creates a voltage that corresponds to the changes in the air velocity of the sound source

Question 9

how do condenser mics work?

Answer 9

• Condenser microphones use a pair of charged metal plates, one fixed (the backplate) and one movable (the diaphragm), forming a capacitor.
• When a sound wave hits the diaphragm, the distance between the two plates changes which produces a change in capacitance.
• The change in capacitance and distance between plates causes a change in voltage potential that can be amplified to a usable level.

Question 10

advantages of condenser mics

Answer 10

Excellent high-frequency and upper harmonic response, can have excellent low-frequency
response.

Question 11

disadvantages of condenser mics

Answer 11

Moderate to very expensive, requires external powering, can be relatively bulky, low-cost
(and some expensive) models can suffer from poor or inconsistent frequency response, two mics of the
same model may sound quite different, humidity and temperature affect performance.

Question 12

condenser mic fallacies

Answer 12

A large-diaphragm condenser has more low end than a small-diaphragm condenser.
A large-diaphragm condenser has a flatter response than a small diaphragm condenser.
A small-diaphragm condenser is quieter than a large-diaphragm condenser.
Condenser mics have consistent response from mic to mic.
A cardioid condenser has a better low-end response than an omni.

Question 13

what is phantom power?

Answer 13

This is a 48-volt DC power source fed by a

recording console, microphone preamp, or DAW interface over the same cable that carries the audio.