Owner`s manual

Limiting

Examine the 99:1 curve in the above graph. This setting reduces all sounds

above the threshold to the same loudness. This is called limiting. Limiting

is usually employed to allow a dynamic signal to be recorded at a maxi-

mum level with no risk that transient peaks will result in overload. In this

application, the threshold setting (usually set relatively high) determines

the extent to which the peaks will be limited.

Dynamic Expansion and Gating

Sometimes, it is desirable to increase the difference between the quietest

signal and the noise in a recording by using a downward expander. A

typical application would be eliminating room noises and breath sounds

that can be heard between the phrases of a recorded vocal part.

The graph below shows the curveÉ<or a downward expander. Notice that

above the threshold, the curve follows a 1 to 1 ratio (i.e., is unaffected by

the gate). For each unit of input change below the threshold the output

changes by two units. This is called a 1 to 2 expansion ratio.

As the input signal drops below the threshold, its output level drops at

twice the rate it would using a 1 to 1 ratio. In effect, sounds below the

expander threshold are “faded out” more quickly than they would be

normally.

OUTPUT

LEVEL

INPUT LEVEL

LOUDER

THRESHOLD

I/O CURVE

1 TO 1 RATIO

2 TO 1 RATIO

4 TO 1 RATIO

8 TO 1 RATIO

99 TO 1 RATIO