Compressor block

Manual

• 5.4 Compressor [CMP]

User contributions

Compressor/Dynamics: tips and tutorials

• Radley's extensive and comprehensible Compression tips
• Compressor FAQ
• Danny Danzi's video tutorial
• Wikipedia

Compressor/Dynamics: X/Y switching

• For X/Y-switching in the Compressor block in the Axe-Fx II you need the XL. Note that there's no MIDI CC available for X/Y switching in the Axe-Fx II.

Compressor/Dynamics: Mix parameter

• Compressors are used mostly as a 100% wet effect. There are compressors with Blend or Mix controls. These can be simulated by using the Mix parameter.

Compressor/Dynamics: Sidechain Select parameter

• You can use the signal that enters the grid to feed the compressor, even if the compressor block is placed further upon the grid, through the Sidechain Select parameter (only in Studio mode).

Compressor/Dynamics: Release parameter (Pedal mode)

• Cliff: "Pedal compressors typically have very long release times so the time is scaled by 10 for pedal mode. The time in studio mode is accurate to within a microsecond." Source
• Cliff: "The times are the classic "time constants" for analog circuits, i.e. the time it takes for a signal to settle to 37% of it's final value (e^-1)." Source

Compressor/Dynamics: Emphasis parameter

• Since the Pedal mode does not have a side-chain, this allows for a similar function by pre-emphasizing the high frequencies prior to compression and then de-emphasizing them after.

Compressor/Dynamics: Fast RMS

• Axe-Fx II firmware 16.02: "Added “Fast RMS” Detector type to Studio Comp type in Compressor block. This detector type mimics the fast detectors in classic rack-mount compressors."

Compressor/Dynamics: operating as a limiter

• There's no dedicated brickwall limiter, but the compressor can be used as such. From the manual: "Setting the RATIO to “INFINITY” turns the compressor into a “limiter,” reducing any level above the threshold to the threshold, applying a sort of “ceiling” or “brick-wall limiting” above which nothing can rise."
• More information in this thread.

Compressor/Dynamics pedal compressor types

• Axe-Fx II firmware 9: "Compressor block now has two Pedal types. “Pedal 1” is the same as before, while “Pedal 2” uses a different algorithm which is smoother and pumps less."
• CPU usage by both "pedal" types is much less than the "Studio" type.
• Axe-Fx II firmware 16.02: "Improved Compressor block by adding a new dynamics processing algorithm. The block has been renamed Comp/Dynmc in light of this. There are now four types of dynamics algorithms: Studio Compressor, Pedal Compressor 1, Pedal Compressor 2, and Dynamics. The Dynamics algorithm allows compression or expansion with a single control. When the Dynamics parameter is set to negative values the block compresses the signal, when set to positive values the block expands the signal."

Compressor/Dynamics: position on the grid

• Placing the Compressor block after the Amp block makes it interfere less with the amp dynamics.

Compressor/Dynamics: heavy pumping compression

• Cliff: "Reduce Look Ahead." Source

Compressor/Dynamics: alternative compressor in Amp block

• Axe-Fx II firmware 15 added an output compressor to the Amp block. You can use this instead of a separate Compressor block.

Compressor/Dynamics: simulating other compressors

• FX8 and Axe-Fx II Effects: Compression, Volume, Gate (CMP, VOL, GTE)
• http://forum.fractalaudio.com/axe-fx-ii-discussion/59925-compressor-settings-country-twang-3.html