Alesis NanoCompressor, Справочное руководство

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Description of Controls
16 NanoCompressor Manual
Ratio
The [
RATIO]
knob controls the amount of compression which will happen once the
input signal crosses the [
THRESHOLD]
level, described above. Ratio controls how
much the input signal will be reduced as a ratio of the input signal level. For
example, if the compression ratio is set for 6:1, the input signal will have to cross the
threshold by 6 dB for the output level to increase by 1dB.
The tick marks around the Ratio control show several ratio settings for reference.
These are, in clockwise order:
1:1 , 2:1 , 4:1 , 8:1 , 10:1 , and :1 . The far right setting, :1
(Infinity to 1), is used for Limiting. This means that the input signal won’t go above
the threshold at all.
Attack
The [
ATTACK]
knob controls the amount of time before compression starts. The
range of this control is 0.1 to 200 milliseconds. The Attack and Release controls only
function when the NanoCompressor is in Peak mode. Long attacks are useful for
percussive sounds, where shorter attacks are good for melodic parts like vocals and
strings. The Attack control is also useful for keeping the transients on percussive
drum or bass sounds. Experiment with different short attack times on snare drums to
get more or less of the “stick” attack.
Release
The [
RELEASE]
knob controls the amount of time the compressor takes to stop
compressing after the signal crosses under the threshold. The range of this control is
50ms to 3 seconds. The Attack and Release controls only function when the
NanoCompressor is in Peak mode. Short release times are good for percussive,
punchy sounds, where longer release times can make compression less obvious on
vocals. Adjusting the release time may be necessary when using extreme
compression and “pumping” or “breathing” is audible, or if lower level signals after
peaks are getting lost.
Pumping and Breathing
When a compressor is making large changes to the input signal (10 to 12 dB or more),
the noise floor will also rise and fall with the signal level. When this noise signal rises
and falls drastically between signals, such as a heavily compressed, noisy drum
track, you might hear the noise level “breathing” between drum hits. One solution to
this breathing problem is to turn up the release time. This way, the noise floor won’t
have time to rise between drum hits.
However, if the Release time is too long, lower level signals after the peak will be lost
as the compressor slowly stops reducing gain. This is called “pumping” as the lower
level signals (noise included) slowly fade back up to their normal signal level. The
secret to avoiding these problems is to achieve a balanced release time on the input
signal.