Chapter 10: Channel View : Gate And Compression; Introduction - Mackie DL806 Reference Manual

Mackie DL806 and DL1608 Reference Guide

Chapter 10: Channel View : Gate and Compression

Introduction

Gates are typically used to reduce leakage from open microphones. Signals below the threshold level are
muted, while signals above the threshold get to pass through. The range control changes the rule slightly.
Signals below the threshold are attenuated by the amount of the range setting, while signals above the
threshold get to pass through.
The operation of the gate is further modified by the attack, hold, and release controls. In order to open
the gate, the trigger signal must exceed the threshold for at least the duration of the attack time. This is
useful for helping the gate discriminate between something that is short duration and long duration,
such as hi-hat leakage into one of the tom-tom mikes.
Once the gate has opened, the hold time begins. The hold timer resets any time the input signal crosses
the threshold again, as long as it remains above the threshold for longer than the attack setting. After the
hold time passes, the gain falls at a rate determined by the release setting. The range control allows the
gate to remain partly open, even if the input is below the threshold.
Compressors are used to reduce or limit transient peaks in a signal. If the signal is too hot, turn it down,
otherwise leave it alone. As the input level to the compressor increases, the output level increases
linearly until the threshold point is reached. After that point, the output level no longer increases linearly.
Instead, it increases at a reduced rate determined by the ratio setting.
The attack and release controls affect the rate of the gain change; attack affects the rate of the onset
of gain reduction and release affects the recovery rate once the transient has passed.
For stereo linked channels, the gain reduction is applied equally to both the left and right side.
There are actually two different types of gates and compressors to choose from on each channel:
clean, surgical modern dynamics and classic sounding vintage dynamics. That's right, you can mix
and match to heart's content! We will dissect both the modern and vintage dynamics separately, but
let's begin by taking a peek at what features apply to both. Modern gates and compressors are discussed
further on pages 69-71, while more information about the vintage gates and compressors may be found
on pages 72-74.
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