Mackie Stereo and Mono Side chain Compressor 사용자 설명서

The red diagonal line added to the graph below, 
represents unity gain (i.e., the output signal is 
the same level as the input signal). Contours 
which are steeper than this, like the segment 
between T and node 1, represent expansion, 
those not as steep, compression.

Expansion occurs when the output level change 
is more than the input level change. For exam-
ple, a 3 dB change in input level, might give a  
4 dB change in output level.

Compression occurs when the output level 
change is less than the input level change. For 
example, a 3 dB change in input level, might 
give a 2 dB change in output level.

Deft use of the nodes allows expansion or com-
pression above the threshold. Expansion can be 
used to increase the volume of quiet passages, 
and bring a little bit more "life" into a perfor-
mance. Note that each individual segment can 
be set as either a compressor, or an expander. 
Just look at the slope between each node. If it 
is steeper than the diagonal, this is expansion, 
and if not so steep, compression.

Note that in the above example, the reduction 
meter and the output level meters are showing 
an increase (expansion) in level.

Having expansion for low input signals, and 
compression for higher signals is a good way to 
level out a signal's dynamics. Quiet signals be-
come louder, and louder signals become quieter. 
We see an example of this below. For input sig-
nals below node 2 in amplitude (approximately 
–28 dB), the dynamics processor acts as an ex-
pander. For signals above node 2, the processor 
is a compressor. 

When you just want to limit the signal to not go 
beyond a certain level, set the end point to be 
the same level as the threshold (Ratio = 
infi nity:1), and keep the Attack time low.