User's Manual

37
®
Compressor (COMP)
A compressor is used to compress the dynamic range of the audio signal, bringing up the lower-level portions of the signal
and restricting the higher-level portions of the signal. In live sound applications, it is common to compress the audio at different
stages in the signal chain. For example, you may apply compression to individual instruments using the mixer’s insert points
and/or a group of instruments using the mixer’s bus or group inserts. You can also apply compression to the entire mix in order
to add some additional “body” to the sound and help “glue” the mix together. It’s this latter application that the compressor
module in the PA2 was designed to address.
Typically, you want to control the dynamic range where it’s needed. For example, using a compressor on an entire mix, without
compressing individual instruments, may not improve a mix where some instruments are much more dynamic than others. The
dynamic instruments still won’t sit right in the mix. You’ll have to increase their volume so their lower-level signals aren’t lost in
the mix and then their louder-level signals will just hit the compressor harder than everything else and suck everything down
with it.
The compressor module in the PA2 is a broadband compressor which provides overall mix compression and is located on the
input processing side of the PA2. The compressor module can help add the final touch of dynamics processing to the mix, but
should be used sparingly as this type of compression generally works best with lower ratio settings. A 1:5 to 2:1 ratio with 2–3
dB of compression should do the trick. It’s subtle, but it can help smooth things out and add a little extra “girth” to the sound
if set properly. Be careful not to apply too much compression, as doing so can have the adverse affect of making the sound
“smaller” or creating “pumping” or “breathing” artifacts.
NOTE: If using subharmonic synthesis, which is placed before the compressor, the strong low-frequency energy from
the sub-synth process can cause excessive compressor pumping/breathing. If you exhibit this type of behavior, try lowering
the subharmonic synthesis level and/or the compression ratio to eliminate the artifacts.
Compressor Parameters
The Compressor menu can be accessed by pressing the COMP button. Turn the DATA wheel to scroll through the list of
parameters. Press the DATA wheel to edit a selection.
• COMPRESSOR [ON, OFF]
Turns the compressor module on or off.
• THRESHOLD [-60 dB to 0 dB]
This parameter sets the level at which the compressor will begin compressing the signal.
The compressor’s Threshold Indicator (shown to the right) indicates when signal is below
threshold, above threshold, or in the OverEasy region. For example, if the threshold
parameter is set to -10 dB, any signal which exceeds -10 dB will be compressed, while
any signal lower than -10 dB will be left alone (uncompressed). Typically, you will want to
set the threshold parameter so that the lower levels of the signal drop below threshold
and the higher levels exceed threshold. This can easily be achieved by looking at the
compressor’s Threshold Indicator and adjusting the THRESHOLD parameter until the
meter alternates back and forth between the
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
and
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
icons (or
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
,
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
, and
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
icons if
OVEREASY is turned on).
THRESHOLD INDICATOR
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
Signal Below Threshold
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
Signal Above Threshold
Preset 1
1
EDIT
COMPRESSOR
HIGH LIMITER
MID LIMITER
LOW LIMITER
30 12 5 0
O
O
O
O
Signal Approaching Threshold
(OverEasy™ Turned On)
• RATIO [1:1 to Inf:1]
This parameter determines how much compression is applied to the signal once it exceeds threshold. For example, applying