PreSonus ACP88 - Manual (Page 21)

BASIC SETUP & APPLICATIONS
19
• Compressing acoustic guitar.
It is sometimes easy to over compress an acoustic guitar because your first impression
is that compression sounds awesome on acoustic instruments. If you're adding the
acoustic instrument to a mix that already includes a lot of other instruments such as
distorted guitar, compressing the life out of your guitar will help you later in the mix. If the
guitar is recorded as a solo instrument or part of an acoustic ensemble, you should
experiment with less compression because you don't want to severely limit the natural
acoustic dynamic range of a good sounding guitar. Start by using the setup described in
the vocal section...
• De-essing using an inserted equalizer into the Sidechain.
A common annoyance when attempting to place a vocal track in a mix is that as you
boost the higher frequencies of the track to 'breathe life' into the vocal, all of the 'SSS's
of the dialogue or lyrics tend to become louder than the rest of the track. A proven
method of reducing this problem is to de-ess the track with 'spectral' compression.
If you don't have an external equalizer, you can use a spare channel of your mixer by
sending the track to both the spare channel and the original channel. Take the direct out
of the spare channel and send it to the Sidechain input of the ACP-88 (signal on the tip
of the tip-ring-sleeve connector). Once patched, setup the compressor as a limiter as
described above. How this works is that when the Sidechain has an inserted signal, the
Compressor generates the Gain reduction from the Sidechain return signal only.
Now, if you boost those frequencies associated with sibilance (SSS),
such as 2kHz to
8kHz, the Compressor will apply the Gain reduction more to the sibilance because it is
now 'seeing' more signal around the frequency of the sibilance. You will need to adjust
the frequency of the equalizer to locate your source of sibilance more precisely.
Parametric equalizers are most effective for this type of compression but you can get by
with most any equalizer.
• Stereo Compressing/Limiting.
The Linking feature of your ACP-88 will allow you to have up to four stereo Linked pairs
of Compressor/Gates. As you may have read in the section in Chapter Two on the Link
function, this is easily achieved by pushing in the Link button on the right-hand channel
thus creating a Linked Stereo Pair. The channel on the left becomes the Master for the
Linked stereo pair and all functions on the Right channel (with the exception of the
Bypass switch) become inoperative. Meters on the right channel will behave as before
but have no significance since the Gain reduction for this channel is being derived from
the Left channel.
To avoid confusion, it might be useful to turn the Compression Ratio to 1:1 on the
channel with the Link button pushed in (the right channel). This will eliminate all Gain
reduction and effectively turn off the Gain reduction meters. The Gain reduction is of
course being derived from the Master channel.
The Link LED indicates when a signal is being passed from the Linked channel to the
Master channel. It will ONLY light up when signal is applied to the Linked channel.