Phase and polarity

Question 1

What does phase describe in relation to waveforms?

Answer 1

Phase describes how ‘in time’ two waveforms are

Question 2

What happens if sound waves are in phase?

Answer 2

Their peaks and troughs line up

Question 3

What occurs when sound waves are out of phase?

Answer 3

Peaks and troughs do not line up, causing destructive interference

Question 4

What does destructive interference cause?

Answer 4

Some degree of cancellation

Question 5

What problem can arise when recording with multiple microphones close together?

Answer 5

Phase issues due to slight time differences between signals

Question 6

What can cause some frequencies to construct or destruct when recording?

Answer 6

Combining signals with phase differences

Question 7

What is one solution to phase issues when recording?

Answer 7

Moving microphones further apart

Question 8

What do polarity buttons do in mixers and DAWs?

Answer 8

Switch the polarity of the signal to solve phase problems

Question 9

How can phase difference be calculated?

Answer 9

In terms of degrees; 0° is the start of a cycle and 360° is the end

Question 10

How can you typically tell if there is a phase issue when recording?

Answer 10

If something sounds thin and lacking in bass