Sound physics, microphone choice and post production

Decibels are used to measure ...............

• The frequency, or pitch, of sound

• The pressure or loudness of sound

• Waves per second

• Speaker and microphone capability

Answer explanation

We measure sound intensity (also referred to as sound power or sound pressure) in units called decibels. Decibels (dB) are named in honor of Alexander Graham Bell, the inventor of both the telephone and the audiometer.

Hertz is used to measure ...........

• The height of a sound wave

• The pressure or loudness of sound

• The frequency or pitch of sound

• Electrical signal strength

Answer explanation

Hertz (Hz) is named after German physicist Heinrich Hertz due to his work with radio waves is a measure of one whole wave cycle per second in terms of frequency.

What does a microphone's polar pattern tell you?

• The angles where it will be most sensitive to sound

• How cold it can get and still work

• The shape of the microphone

• The shape of the diaphragm

Answer explanation

A polar pattern is the space around a microphone where it is the most sensitive to sound. Different microphones have different polar patterns, and these patterns play a role in determining their best uses.

What kind of polar pattern is represented in this image?

• Omnidirectional

• Bidirectional

• Super cardioid

• Cardiod

Answer explanation

Microphones with a cardioid polar pattern pick up quality sound in a heart-shaped pattern in front of the microphone. The sides of the microphone are less sensitive but will still pick up a usable degree of sound at a closer range, while the rear of the microphone is entirely out of range.

Which of the images below represents a bi-directional polar pattern?

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• 
• 
• 

Answer explanation

A bidirectional mic, also called a figure-of-eight, is equally sensitive to sounds coming from the front and rear of the mic and least sensitive to sounds coming from the sides.

Which two words below describe types of microphones

• Dynamic

• Desiccant

• Incandescent

• Condenser

Answer explanation

Condenser microphones are sensitive, need a power source and are useful for studio recording where noise can be controlled.

Dynamic microphones are less sensitive, more sturdy, do not need external power and are useful for field or stage recording.

Which two statements are true about this microphone?

• It has an omnidirectional polar pattern

• It has a bi-directional polar pattern

• It is known as a lavalier or lapel microphone

• It is known as a shotgun microphone

Answer explanation

A lavalier, lav, or lapel microphone is often fastened to a person's clothing. It is best located close to the sound source and often has an omnidirectional polar pattern so that it can still detect sound if a person moves their head.

Which two statements are true about a condenser microphone?

• It is very sensitive and best used in environments where sound can be controlled.

• It can handle rough treatment and can be thrown around on stage without being damaged.

• It can operate without a power supply.

• It is also known as a capacitor microphone.

Answer explanation

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 an electrical characteristic called capacitance.