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FX Loop block (legacy)

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Revision as of 21:38, 8 February 2018 by Yek (talk | contribs)
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The information on this page supplements the official manuals.

Axe-Fx XL Plus rear.png

FXL: supported by which Fractal Audio products?

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

FXL: X/Y switching or channels

  • Axe-Fx III: n/a.
  • Axe-Fx II: no.
  • FX8: n/a.
  • AX8: no.

What does FXL do?

FXL is used to enable the effects loop on the Axe-Fx II and AX8: Input 2/Effects Return and Output 2/Effects Send. You can use this for a 4CM rig, to connect a second instrument or sound source, to insert a stomp box or rack device, to enable multiple output signals etc.

Use FXL to:

  • let a signal from Input 2 (Effects Return) enter the grid.
  • send a signal through Output 2 (Effects Send).

FXL versus Echo Output 2

The Echo Output 2 parameter in the I/O menu on the Axe-Fx II and AX8 provides an alternative way to activate Output 2. It copies the signal from Output 1 and sends it through Output 2. The Output 2 Mode determines if it's a stereo or mono signal.

But: if a preset contains the FXL block, the parameter "Echo Output 2" is always ignored.

FXL on Axe-Fx II and AX8

The functionality is the same.

The Axe-Fx II however has a sensor on Input 2. If nothing is connected to Input 2, the effects loop will not run, which prevents feedback loops. source

The AX8 doesn't have this sensor. This means that on the AX8 you always have to put FXL in a branched off (parallel) path, if you use it for a separate output signal.

Route a signal from Input 2 to Output 2

This works with the Axe-Fx II only because the Feedback Send/Return blocks are required.

You can add an instrument, music player etc. to Input 2 and send its signal to Output 2 as follows:

  1. Connect the external gear to Input 2.
  2. Select the correct Input Mode for Input 2 in I/O > Audio.
  3. Add a Feedback Return block to a separate row. Set Mix and Level to 100, to start with.
  4. Add a FXL block after Feedback Return (and effect blocks if desired). Set Level at 100.
  5. Add a Feedback Send block after FXL, with Send at 100.
  6. Turn up Output Level on the front panel to get signal out.

The described routing lets the signal from Input 2 enter the grid through FXL, to be processed by the effect blocks after FXL. FXL's Level parameter sends signal to Feedback Send, which routes the signal back to Feedback Return. From there it enters FXL again, but this time to send the signal to Output 2.

If you want this routing to go to Output 1 as well, connect Feedback Send to the grid's output. But be aware that this causes extremely loud and high-pitched feedback when nothing is connected to Input 2 !!

If you want to add signal from Input 1 to Output 2, connect that row to FXL.

More FXL tricks

The FXL block is stereo, so by panning you can have an external loop and still use the FXL's auxiliary output.

Mr_Fender: "Put the FX Loop block in front of the amp block and hard pan the signal going into the FX Loop block from that row hard left. In the amp block, set input select to left only. Put a feedback send block before your cab block. Put a feedback return block in another row before the FX loop block and set its balance to hard right. Connect the feedback return block output to the FX Loop block input. The rear Input 2 L and output 2 L jacks are then used for pre-effects and output 2 R is used to feed your power amp and cab on stage. The front panel output 2 knob will control both sides together, so you'll have to play with the levels in the FX loop and feedback blocks to get it all set right."

Bakerman: "t's possible to use the FX Loop as two mono loops in series, with a certain routing using feedback send/return."

More information about FXL

  • The Level parameter in the FXL block affects the signal flow to the block AFTER the FXL block, not the signal to OUT 2.
  • If you use FXL as an auxiliary output (OUT 2) and connect it to the end of the grid, turn down its Level to prevent passing signal to OUT 1.
  • The FXL block's output level is stored per scene.
  • How to change FXL from stereo to split.
  • You can use the FXL block to integrate computer effects. Set I/O > USB Digi Source to: OUT 2. source