Filter block

The information on this page supplements the official manuals.

Image to be added

Filter: supported by which Fractal Audio products

• Axe-Fx III: 4x.
• Axe-Fx II: 4x.
• FX8: 2x.
• AX8: 2x.

Filter: X/Y-switching or channels

• Axe-Fx III: 4 channels.
• Axe-Fx II: no.
• AX8: yes.
• FX8: yes.

When to use a filter

A filter is a very versatile effect. Possible applications include:

• One-band equalizer.
• Boost the input of an amp block.
• Boost the overall signal level for leads.
• High-pass or low-pass filter.
• Envelope filter / auto-wah.

Filter types

Variable-Q

Many “classic” graphic equalizers use variable-Q designs which may be more familiar to some users as opposed to constant-Q filters. In the Filter block this type is selected by choosing the “Peaking2” type.

Analog shelving EQ

“Lowshelf 2” and “Highshelf 2” recreate the analog shelving filters found on classic mixing consoles. These filters are somewhat quirky and exhibit “overshoot” which gives them a certain musical quality. Set the Q between 0.5 and 0.707 to recreate those classic sounds or experiment with the Q for different amounts of overshoot. These filter types are great for getting that massive sound associated with passive equalization.

Tilt EQ

Tilt EQ is a slope filter that allows broad adjustment of the tone using just two parameters: Frequency and Gain. The Gain parameter sets the maximum gain of the filter relative to the center frequency. For example, a gain of 10 dB would set the maximum gain to 10 dB. The gain at the center frequency would be 0 dB and the minimum gain would be -10 dB, therefore a total of 20 dB of EQ would be applied.

Notch

"Gain doesn't apply to a notch filter. Only frequency and Q are relevant." source

Filter examples

Envelope Filter (Auto Wah)

Fractal Audio processors don't have a dedicated Envelope Filter (Auto Wah) effect block. You can achieve this effect by attaching an Envelope to a Filter or Wah block.

• Example.
• Example.
• Axe-Change.

Or try the "Psychadelic Duck" preset (Axe-Fx II).

Mid-Boost

To emulate the Eric Clapton / Fender Mid-Boost:

"Use the Filter block. Since the max boost is 25 dB set the filter order to 4th which will give you a maximum of 24 dB. Set the type to Peaking. Set freq to 500 Hz. Vary gain and Q to taste." source

Clean Boost

Set the Filter to "Null", set its Level to where you like it, put it at the end of the signal chain, and assign a switch. Now you have a simple, low-CPU clean boost at your disposal.