Chorus block

Chorus: in the owner's manuals

• Axe-Fx II: 5.3 Chorus [CHO]s
• Axe-Fx II: 5.25 Quad Chorus [QCH]s
• FX8: ...
• AX8: ...

Chorus: supported by which Fractal Audio products?

• Axe-Fx II: yes.
• FX8: yes.
• AX8: yes.

Position of the Chorus block on the grid

• It's a matter of personal preference where you want to put the Chorus block: before ("pedal") or after ("rack") the Ampblock. When placed before the Amp, make sure the Chorus is set to mono (LFO Phase is 0, default).
• When set to the Dimension type, the block should be placed after the Amp block for best results (stereo).

Mono/stereo output of the Chorus

• Chorus is a stereo effect, but defaults to mono to prevent phase problems when placed before an Amp. To make it stereo: set LFO Phase to 90 or 180.
• Some chorus types (such as 80s and Triangle) invert the wet sound on one side. If you're collapsing to mono the wet will cancel and you'll hear no chorus.

Number of Chorus voices

• Selecting more than 2 voices is useful only when LFO Phase is not zero. source

Vintage Tape Chorus

• This Chorus type uses the tape delay algorithm which is used in the Delay block. This type sums the left and right block inputs into mono, so use caution as stereo cancellation may occur.

Dimension D Chorus

• Based on Roland's Dimension D SDD-320.
• Original manual.
• Cliff's comments:
  • "The Dimension Mode parameter turns on "Dimension Processing". This can be turned on in any type. However I highly recommend using the Dimension Type as it sets the correct base algorithm, LFO type, delay time, phase, etc., etc. as well as turning on the Dimension Processing. The Dimension D is really just a typical chorus. At the output, however, some special processing occurs that gives that unique sound. Turning Dimension Mode to one of the three settings engages the various aspects of that processing." source
  • "A Dimension D is a fairly typical chorus with some added analog processing on the outputs. The analog processing has a "normal" mode and a "boost" mode. The unit itself has four switches. These switches set the rate and the depth as well as turn on the boost mode. The switches do the following: Slow rate (0.25 Hz), low depth. Slow rate, normal depth. Fast rate (0.5 Hz), normal depth. Fast rate, normal depth, "boost" on. The depth is actually reduced in modes 3 and 4 to compensate for the higher rate. In the Axe-Fx this is done automatically when Auto Depth is on. Therefore I've indicated the depth as "normal" in modes 3 and 4 as the amount of pitch shift is roughly the same as mode 2. There is also an EQ that is present in all the modes on the dry signal. The LFO is a triangle wave and is 180 degrees out of phase between channels. The Dimension Mode parameter has three settings: Low, Medium and High. Low: Dry EQ off, boost off. Med: Dry EQ on, boost off. High: Dry EQ on, boost on. The Low setting has no equivalent on an actual Dimension D since the dry EQ is always active. The Dimension Type sets the LFO type, phase, Auto Depth, Hi Cut, etc., etc. and sets the Dimension Mode to Medium. With the appropriate settings of Rate and Depth you can duplicate modes 1, 2 & 3 on the actual Dimension D. To duplicate mode 4 you simply set the Dimension Mode to High. The Rates are given above. I've found a Depth of around 25% to be a good starting point. Increase or decrease to taste. The Type does NOT preset the Rate or Depth." source
  • "Dimension 1 is the same as previous firmware and is "digital". Dimension 2 (firmware 17 and later) uses the new BBD algorithm." source

Chorus BBD

• The Chorus block in Axe-Fx II firmware 17 and later (including AX8) has a new algorithm based on the BBD algorithm developed for the Flanger block. All the “Analog” chorus types use this algorithm.

Vibrato effect

• There's no dedicated "vibrato" effect in the Axe-Fx II and AX8. You can create this using a 100% wet chorus.
• A classic "VB" pedal vibrato effect typically uses a TRIANGLE waveform for the LFO, but the classic "CE" vibrato uses SQUARE.
• Matt Picone: "A Vibrato effect causes pitch to vary periodically, creating a "warble." This can be created easily on the Axe-Fx using the Chorus block set for mono and the Mix at 100%. Vibrato depth and rate may be set as desired. You may wish to set chorus Auto Depth to "OFF" for more dramatic vibrato effects."
• Forum member Scarr: "For any "vibrato mode" conversions, turn the mix to 100%. The rumour is just the Boss VB-2 was a CE-2 without the dry signal mixed in (and pedal ramp on depth). A switch to disable the dry signal is a popular CE-2 mod."

Various Chorus tips

• Forum member and effects wizard Simeon provides a load of magnificent delay effects, including chorus. Leave a donation if you use them.
• Javajunkie's recreation of the Boss CE-1 Chorus and Vibrato tones.
• Chorus in Wikipedia.
• Vibrato in Wikipedia.