ALESIS 03D User Manual

Page 166

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156

Chapter 14—Dynamics Processors

03D—Owner’s Manual

THRESHOLD

—This determines the input signal level at which compression and

expansion are applied. Signals at a level below the threshold+width are attenuated by
the expander. Signals at and above the threshold level are compressed by the amount
specified using the Ratio parameter. The trigger signal is sourced using the KEY IN
parameter.

RATIO

—This determines the amount of compression. That is, the change in output

signal level relative to change in input signal level. For a 2:1 ratio, for example, a 10 dB
change in input level (above the threshold) results in a 5 dB change in output level. For
a 5:1 ratio, a 10 dB change in input level (above the threshold) results in a 2 dB change
in output level. The expander ratios are fixed: 1.5:1 for the soft compander and 5:1 for
the hard compander.

WIDTH

—This determines how far below the threshold level expansion is applied. The

expander is essentially turned off when the width is set to 90 dB.

ATTACK

—This determines how soon the signal is compressed and expanded once the

compander has been triggered. With a fast attack time, the signal is companded almost
immediately. With a slow attack time, however, the initial transient of a sound passes
through unaffected. Attack times from 1–5 ms are a good place to start.

RELEASE

—This determines how soon the compressor and expander return to their

normal gains once the trigger signal level drops below the threshold. If the release time
is too short, the gain will recover too quickly causing level pumping (i.e. noticeable gain
fluctuations). If it is set too long, the compressor may not have time to recover before
the next high level signal appears, and it will be compressed incorrectly. Release times
from 0.1–0.5s are a good place to start.

OUT GAIN

—This sets the compander’s output signal level. It can be used to compen-

sate for the overall level change caused by the compression and expansion processes.

ATTACK

0–120 ms (1 ms steps)

RELEASE

5 ms–42.3 s (sampling rate @ 48 kHz)
6 ms–46 s (sampling rate @ 44.1 kHz)
8 ms–63.4 s (sampling rate @ 32 kHz)

OUT GAIN

–18 dB to 0 dB (0.5 dB steps)

Parameter

Range

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