Microphones

Question 1

A microphone is a ……….

Answer 1

Transducer

Question 2

The sensitive transducer element of a microphone is called it’s …….

Answer 2

Capsule

Question 3

DYNAMIC MICROPHONES
Dynamic microphones are sometimes known as …… …. ………..

Answer 3

Moving coil microphones

Question 4

DYNAMIC MICROPHONES
How do dynamic microphones work

Answer 4

• A movable coil is positioned in a magnetic field, attached to a diaphragm
• The diaphragm is a thin piece of material that moves in response to the changes in air pressure
• when sound enters the microphone, the diaphragm vibrates
• the coil moves in the magnetic field and a varying electrical current is induced that is proportional to the changes in air pressure
• this is called electromagnetic induction

Question 5

DYNAMIC MICROPHONES
What are some pro’s to dynamic microphones

Answer 5

Can withstand high SPL/volume
Resistant to moisture
Less likely to create feedback
Good for live use

Question 6

DYNAMIC MICROPHONES
What are some pro’s to dynamic microphones

Answer 6

Can withstand high SPL/volume
Generally inexpensive
Takes the edge off sound making it sound warmer
Resistant to moisture
Less likely to create feedback
Good for live use

Question 7

DYNAMIC MICROPHONES
What are some con’s to dynamic microphones

Answer 7

Limited HF response
Not very sensitive

Question 8

CONDENSER MICROPHONES
Condenser microphones contain a capacitor which in turn consists of … plates

Answer 8

2

Question 9

CONDENSER MICROPHONES
How do condenser microphones work

Answer 9

• sound causes one of the plates to vibrate which functions as a diaphragm
• when the diaphragm vibrates, the gap between the 2 plates changes
• the capacitor plates are powered
• moving the diaphragm causes a change in capacitance and thus a current flows

Question 10

CONDENSER MICROPHONES
what are some pro’s to condenser microphones

Answer 10

Sensitive
Captures a wide frequency range
Captures a brighter signal than dynamic mic’s
Good signal to noise ratio
Wide dynamic range

Question 11

CONDENSER MICROPHONES
What are some con’s to condenser microphones

Answer 11

Requires phantom power
Can’t handle high SPL
More likely to produce feedback

Question 12

RIBBON MICROPHONES
How do ribbon microphones work

Answer 12

• Sound vibrations disturbance metallic ribbon suspended in a magnetic field
• this generates a voltage that is proportional to the movement of the ribbon

Question 13

RIBBON MICROPHONES
What are some pro’s to a ribbon microphone

Answer 13

Very sensitive
Can handle high SPL
flat frequency response

Question 14

RIBBON MICROPHONES
What are some con’s to ribbon microphones

Answer 14

Fragile
Very expensive
Damaged or broken by phantom power

Question 15

Phantom power has .. volts

Answer 15

48

Question 16

What microphone uses phantom power

Answer 16

Condenser microphones

Question 17

What is gain

Answer 17

The amount of boost applied to the pre-amp stage of an audio channel

Question 18

What is gain used for

Answer 18

Boost signals to an operative level
Boost beyond that point to drive a signal into distortion for musical purposes

Question 19

What is a pad

Answer 19

A switch on equipment that ettenuates the gain by a set amount to prevent clipping

Question 20

What is polarity

Answer 20

Inverts the polarity of the signal

Question 21

What do clip/activity/LEDS’s do

Answer 21

They illuminate when a signal is clipping or distorting and when a signal is going through a channel

Question 22

What is phantom power

Answer 22

It provides power to active electronic devices