In this video, we’ll continue to explore the Virtual View of AVX Architect and look at the Compressor object. The Compressor is found in the virtual view, under the “Dynamics” section of the audio processing objects. The Compressor reduces the level of signals that go above a threshold level. This compressor features the classic BSS 'progressive knee' sound, which produces a gentle ratio near the threshold becoming progressively more aggressive further into compression.
Let’s look at some of the parameters in the Compressor factory panel. The “Enable” button here in the center will turn on the compressor processing. When this is off, the compressor will not change the signal, acting as a bypass.  The “Threshold Control” adjusts the level threshold above which compression will take place. Below this threshold, no compression will take place. “Ratio” will adjust the aggressiveness of the compression. “Attack” adjusts the time it takes for the compressor to respond after the signal level goes above the threshold.  “Release” adjusts the time it takes for the compressor to recover after the signal falls below the threshold. Remember that the compressor can cause distortion if the Attack and Release times are too fast since it will be trying to apply dynamic gain reduction to the instantaneous values of lower frequency waveforms. The “Gain” control is used to increase the gain at the output to make up for any gain reductions from compression. An auto-release mode not only allows the release time to be related to the user-set attack time, but also varies this relationship depending on the nature of the program to give a very natural sounding result. This Gain Reduction meter will display the amount of gain reduction being applied.
At the top of the factory panel, we have our usual object name, lock button, and selection mode switch. On the right, the “Properties” window has the usual naming, workspace location, and DSP allocation options. The “Options” section contains the usual channel count of the object block. Dynamics processing objects like compressors or gates are limited to a maximum of 128 channels. When using multi-channel compressors, the “Mode” can be changed between independent and shared. When independent, each channel gets compressed based on the signal level of its own input. In shared mode, all channels get compressed simultaneously based on the signal level of the loudest input. The “Side Chain” option is off by default. Turning it on will add an input source to our compressor object labeled as side chain. The Compressor will then listen to our side chain input, and processing on our main input source will be controlled and dynamically affected by the sidechain input. When using side chain on multi-channel compressors, the sidechain input will control the compression of all channels.