Dynamics

Question 1

What does a compression ratio of 4:1 mean?

Answer 1

Once past the threshold, the input signal must increase by 4dB for the output to increase by 1dB.

Question 2

Compressor attack time is defined as:

Answer 2

The time it takes for the compressor to enter full gain reduction.

Question 3

Signals below the compressor threshold pass through without being compressed:

Answer 3

True.

Question 4

If a compressor is showing 10dB of gain reduction and you add 10dB of makeup gain, lower level signals below the threshold will be:

Answer 4

10dB louder.

Question 5

Signals below the threshold of a downward expander are:

Answer 5

Reduced by the downward expander ratio.

Question 6

A soft knee compressor starts compression before the threshold:

Answer 6

True.

Question 7

When will a soft knee compressor be at the full compression ratio?

Answer 7

After the threshold.

Question 8

What can be said about the output level at the threshold of a soft knee compressor compared to that of a hard knee compressor?

Answer 8

It has a lower output level.

Question 9

Gate attack time is defined as:

Answer 9

The time it takes for the gate to come out of gain reduction.

Question 10

A parametric EQ with a bandwidth of 1/4 octave inserted into the side chain of a compressor with a boost of 6dB at 1kHz will cause the compressor to compress a signal at 1kHz more than a signal at 100Hz:

Answer 10

True.

Question 11

An optical compressor uses what for the gain element?

Answer 11

Photo diode and LED.

Question 12

A compressor is set to a 3:1 ratio. The threshold is set at +3dBu. If the input signal is at +12dBu, what is the level of the output signal?

Answer 12

+6dBu.

Question 13

A gate has a look-ahead time of 600uSec. What does this mean?

Answer 13

The main signal will be delayed by 600uSec so that the gate will have time to open before the signal passes through the gain element.

Question 14

What will be the result of running the kick drum into the key input of the bassist’s gate?

Answer 14

The bass will only be heard when the kick is played.

Question 15

An acoustic guitar player switches between strumming and finger picking in the same song. His strumming peaks at 8dBu. How should the compressor be set to make his finger picking 8dB louder than his strumming?

Answer 15

Adjust the threshold and ratio until you have 8dB on the gain reduction meter when he is strumming and no gain reduction when he is finger picking, then add 8dB of make-up gain.

Question 16

You are using a digital limiter. The A/D of the digital compressor reaches it’s max output when the input signal is at +22dBu, and the box is unity gain. Assuming no other gain through the unit, at what threshold must you set the digital limiter so that the output signal will not exceed +10dBu?

Answer 16

12dBFS.

Question 17

If a downward expander is set at a ratio of 1:1.5, a threshold of 40dBu, and a max attenuation (or depth) of 20dB, how much gain reduction will there be if the input signal is at 50dBu?

Answer 17

15dB.

Question 18

Compression ratio of 2:1. Compressor threshold of 10dBu. Limiter threshold of 0dBu. If the input signal is at +10dBu, how much gain reduction is being contributed by the limiter?

Answer 18

None.

Question 19

What should you do If you want to duck music when someone talks into a mic?

Answer 19

Send the music through a compressor with the mic plugged into the side-chain insert.

Question 20

A hi-shelf EQ is inserted into the side-chain of a compressor. The EQ is set to cut 10dB at 5kHz with a slope of 18dB/octave. The compressor is set to 2:1 at a threshold of -10dBu. If the input signal is +10dBu at a frequency of 10kHz, what is the level of the output signal?

Answer 20

5dBu.

Question 21

Which compressor settings will most accentuate the transient attack of a snare drum?

Answer 21

Fast release and slower attack.

Question 22

On a Multi-band compressor/limiter, setting the threshold of each band’s limiter to 0dBu will ensure that the output will not be above 0dBu:

Answer 22

False.