PreSonus ACP88 - Manual (Page 20)

BASIC SETUP & APPLICATIONS
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If you consider the sound of a snare drum, you will notice the sound has a beginning
loud sound (transient) followed by a sound of decreasing intensity (decay). Patch a
channel of your ACP-88 for compressing the snare drum as described above and we
can explore some dramatic changes that compression can have on the snare drum's
sound.
For a simple setup, make sure that: Soft button is out; Auto button is out; Ratio is set to
4:1 on the legend; Attack is fully counterclockwise; Release is straight up at the 12:00
o'clock position; Gate Threshold is fully counter-clockwise; Link button is out and the
Bypass button is out. Adjust the Threshold until you see about -lldB on the gain
reduction meters. At this point, the snare's volume is simply lowered by lldB. Now slowly
raise the Attack time by turning the
Attack knob clockwise. You should notice that the beginning 'transient' of your snare
sound is starting to jump out of the speakers and slap you in the face. This becomes
even more noticeable when using digital reverberation on the snare.
Now you can adjust the Gate on the snare to stop those other drums from 'bleeding'
through the snare mic: Begin by adjusting the Attack time of the Gate to .01(10
microseconds) by turning the Gate Attack control knob fully counter-clockwise. Turn the
Gate Release knob to about the middle position, set the Gate Range to 60dB (Range
Button pushed-in), adjust the Gate Threshold slowly clockwise until you begin to hear
those other drums disappearing. Too high of a Threshold setting might disrupt the snare
drum's natural sound, a Threshold setting that is too low will let the sound of the other
drums open the Gate. You need to adjust the Gate Threshold and Release to suit your
drumming taste.
This simple application applies to any percussive instrument, of course. Experiment.
• Limiting.
Limiting is defined as compressing with a Ratio of infinity to one. This setting acts like
an imaginary ceiling for the level of a signal. On your ACP-88, Limiting occurs when the
Ratio knob is fully clockwise. At this point, the Threshold knob essentially becomes the
'ceiling' knob for the channel. You will most likely want a virtually instantaneous Attack
time while Limiting. To achieve this: Make sure the Auto button is out, Turn the
compressors Attack time knob fully counterclockwise and set the compressor's Release
time for the most natural sounding decay for whatever input signal you are using.
(Warning: Improper settings of the Release time have been known to cause pumping,
breathing and coughing in limiters. Consult your ears when fine tuning.)
Compressing bass guitar.
Very similar to compressing vocals, the bass guitar is almost always compressed or
limited during recording. Start with the setting described above for vocals. Vary the
Compression Ratio, Attack and Release to suite your taste.