Calrec SUMMA User Manual

Also see for SUMMA: Installation manual Installation manual Quick start guide

Contents

Calrec SUMMA User Manual Manual pdf 124 page image

A gate is effectively an extreme version of an expander, with a very high ratio, resulting in the gain of the input signal beingsignificantly reduced almost immediately as it falls below the threshold. Gates are often used to minimise unwanted audiocontent.Calrec expander/gates have 6dB of built-in hysteresis to avoid unwanted ‘chatter’ (constant on/off switching) resultingfrom an input signal residing on or around the threshold.Global Module ControlsWhen looking at a dynamics module, any control situated within the window header affects the whole module, i.e thecompressor/limiter and expander/gate together. This includes the following:• Each Dynamics module can be inserted either pre EQ, pre fader or post fader. Tap the dynamics position button inthe window header and select an option.• By default, dynamics modules operate as standalone units. The third button in the window header allows the moduleto be put into one of eight Dynamics Links.• Dynamics modules can be bypassed by tapping the BYPASS toggle switch in the window header.FIGURE 2 - GLOBAL DYNAMICS CONTROLSDynamics LinksDynamics Links allow multiple audio feeds to have the same dynamics processing applied. When multiple paths’dynamics modules are set to be part of a Dynamics Link, the amount of gain reduction applied across the link will alwaysequal that for the signal which is being affected the most. For example, within a Dynamics Link, if one path’s signal iscausing 5 dB of gain reduction and another is causing a reduction of 10 dB, all signals within the Dynamics Link will havea gain reduction of 10 dB applied. When expander/gate units are used within a Dynamics Link and one feed within thelink reaches the threshold level to open the expander/gate, all expander/gates within the link open regardless of the audiolevels of their feeds.Compressor/Limiter Controls• Threshold: The level (dBFS) at which the signal will begin to have its gain reduced.• Ratio: Controls gain reduction once a signal has exceeded the threshold, for example, if the ratio is set at 2:1 andthe signal exceeds the threshold by 4 dBFS, the gain will be reduced so it exceeds the threshold by only 2 dBFS.When set to 50:1, the compressor is acting as a limiter.• Make Up Gain: Allows the gain of the whole compressed signal to be increased by up to 20 dB.• Attack: Time taken to reduce the gain to reach the new compressed level. Short attack times enable the compressorto catch transients in the audio feed, whereas increasing the attack time will focus the compressor on more long termlevel issues, such as level differences across various sections of a program.• Release: Time taken to remove gain reduction once the signal falls back below the threshold. Short release timescan lead to a ‘pulsing’ effect, with only audio peaks being compressed. A longer release time will lead to a smoothereffect at the expense of some lower level audio components being compressed.124 SUMMA Networked Audio Production System PROCESSING