I/O Configuration

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I/O Configuration

Press the I/O button to access the I/O configuration menus. These menus allow you to configure the audio, MIDI and pedals of the Axe-Fx.

Mode Configuration

The first page of the I/O menu configures the primary input source. Setting the INPUT SOURCE to ANALOG FRONT or ANALOG REAR configures the unit to slave all clocks to the internal 48 kHz word clock. Setting to DIGITAL selects the DIGITAL input as the main input and slaves all clocks to this bit stream. The Axe-Fx can only run at 48 kHz. If you connect a digital source to the unit be sure that its sample rate is 48 kHz. Set the INPUT SOURCE to ANALOG FRONT when using the front-panel input. This input is conditioned to provide optimum noise performance for use with an electric guitar. Set the INPUT SOURCE to ANALOG REAR when using the rear-panel input. This input is a generic line-level input and works with any line-level source.

Audio Configuration

The next page of the I/O menu configures the inputs to the Axe-Fx. Select the desired mode for each of the inputs as follows: LEFT ONLY - Use for monophonic input sources. For INPUT 1 use the front panel INSTR jack or the rear panel INPUT1 - LEFT / MONO jack (set INPUT SOURCE as described above). For INPUT 2 use the rear panel INPUT2 - LEFT / MONO jack. In this mode the left input signal is copied to the right channel. L+R SUM - Use when you wish to sum two sources using the LEFT and RIGHT input jacks. STEREO - Select this if your input source is stereo.

MIDI Configuration

The MIDI page configures the MIDI parameters and preset mapping of the Axe-Fx. The Axe-Fx contains memory for 384 presets. From a MIDI standpoint these presets are arranged in 3 banks of 128 each. To recall presets above 127 your MIDI device must be capable of transmitting a MIDI Bank Select Coarse controller message (controller #0). The value of this message selects the bank (0 - 2). Subsequent MIDI Program Change messages access programs from the selected bank. MIDI CHANNEL - Selects the MIDI channel to which the Axe-Fx will respond. If set to OMNI the Axe-Fx will respond to MIDI messages on all channels. PROG CHANGE - When set to ON the Axe-Fx will respond to MIDI Program Change messages. When set to OFF it will ignore them.

MAPPING MODE - When set to OFF the Axe-Fx will recall the preset given in the Program Change message. When set to CUSTOM you can set up a custom map where an incoming number is mapped to a desired preset MAP FROM - Sets the input MIDI Program Change number that is mapped. MAP TO - The actual preset that is recalled when the MAP FROM number is received. NOTE: Mapping is only supported within Bank A (presets 0 - 127). SYSEX ID - Sets the System Exclusive ID of the unit.

Control Configuration

The CTRL page configures the external control capabilities of the Axe-Fx. Each item in the list can be controlled by either of the pedals or by a MIDI continuous controller. To set up the control for an item simply turn the value dial to select the MIDI continuous controller number (or desired pedal) that will control that item. The Axe-Fx has a “learn” feature that allows it to detect the controller. Simply select the desired item to control and press ENTER. Now move the controller and the Axe-Fx will learn the controller number.

  • Example

To set the main output volume to be controlled by Pedal1 select OUT1 VOLUME with the navigation buttons. Then turn the value dial to select PEDAL1. Alternatively press ENTER and then move your pedal connected to the PEDAL1 jack until the Axe-Fx learns the source.

In the list there are eight external controllers labeled EXTERNAL 1, EXTERNAL 2, etc. These are the external sources that can be attached to controllable parameters. The actual source can be either of the PEDAL inputs or any MIDI continuos controller.

  • Example

Manual control of effects like Wah requires an external controller to be attached to the Wah’s CTRL knob. In this example we’ll assume an expression pedal is connected to the PEDAL 2 input jack. The first step is to assign PEDAL 2 to an external controller. In this case we’ll use EXTERNAL 1. To do this select EXTERNAL 1 with the navigation buttons and turn the value dial until PEDAL 2 is displayed (or use the Auto-Learn function). Now when you attach a modifier to the Wah’s CTRL knob simply select EXTRN 1 as the control source.

In this example we could have used any of the eight external controllers or any MIDI continuous controller. The main point to understand here is that there are eight logical external control sources. Each source is assigned to a physical source via the CTRL menu page. This source can be the PEDAL inputs or a MIDI continuos controller. The logical source is then attached to an effects parameter (via the MODIFIER menu, see the Controllers and Modifiers chapter).


GLOBAL BYPASS - The Global Bypass controller is a special type of bypass control. Whenever the Axe-Fx receives a Global Bypass controller message it toggles the state of any effects that were bypassed in the current preset. For example, if a preset has a Wah in it and that preset is saved with the Wah in a bypassed state the Global Bypass message would un-bypass it. This controller can be used as a universal master bypass control that toggles the bypassed blocks for each preset. Normally you would have to remember what effect is bypassed in a preset and then send the appropriate controller for that effect. With the Global Bypass, however, you can use a single controller to toggle effects for each preset on and off. For some presets you may have a Drive block that you wish to toggle on|off to switch between rhythm and lead work. For others you may have a Wah or Flanger or whatever that you wish to toggle. So instead of having to use a different controller for each preset you can simplify and just use one.

When a preset is recalled the effects are in the bypass state that they were stored in. Any that are bypassed may then by activated using either their individual bypass controllers or all may be activated by using the Global Bypass. EFFECT BYPASS - Each effect in the Axe-Fx can be toggled in and out of bypass using a MIDI continuous controller. Following the Global Bypass item are the individual bypass controllers. Simply set the value to the desired controller number (or pedal number).

  • Example

To control the bypass state of Flanger 1 use the navigation buttons to select FLANGER 1 BYP. Then turn the value knob (or press ENTER to automatically learn) to select the desired controller number. In this example we’ll use CC# 12. Now whenever the Axe-Fx receives a CC# 12 message the bypass state of Flanger 1 will be set to the value of the controller. Note that the Axe-Fx uses negative logic for the bypass state. A controller value of zero bypasses the effect and non-zero the effect is active. So if the controller value equals zero, effect off, controller value greater than zero, effect on. Pedal Configuration

The PEDAL page configures the pedals. The pedals can be used for parameter control, volume control, effect bypass, preset switching and other purposes. When used for preset switching the Axe-Fx can change presets without the use of a MIDI controller.

The two pedal jacks on the back of the Axe-Fx support continuous, momentary or latching pedals. Continuous pedals are normally used for real-time continuous control of effect or global parameters (i.e. volume). The other types are normally used for bypass control or preset switching. It is important to understand how the various pedal modes operate to use them to the ultimate capability.


To use the pedal for switching operations such as bypass or preset change be sure to set the pedal type to match the type of footswitch. Momentary footswitches close a contact while the pedal is depressed. They typically do not "click" when pressed. Latching footswitches alternate between contacts closed and opened each time the switch is depressed, they usually click. Internally the Axe-Fx stores a state for the pedal. For momentary footswitches depressing the switch toggles the internal state between 0 and 1. When set to latching the state of the contacts sets the internal state: contacts closed = 0, contacts open = 1.

Footswitches are normally used to control an effects bypass state or for preset increment/decrement. Of course one can still assign a footswitch as an external controller but the "value" from the switch will be either 0 or 1. This may be used, for example, to change the rate of a Rotary simulator between two speeds, when the controller is at value 0 the rate would be slow and when at 1 the rate would be fast. This would be setup using a modifier on the Rotary simulator rate control. When using a footswitch to control preset recall, a change of state causes a preset change. For example, if a momentary footswitch is connected depressing the switch toggles the internal state. This in turn would increment/decrement the current preset if configured as such. However, if a latching footswitch were connected but the type is incorrectly set to momentary then the preset would only change every other time the pedal was depressed as it would interpret the first press as the pedal being depressed and the second press as the pedal being released.

If the pedal type is set to continuous it CANNOT be used to control bypass or preset change. This prevents unwanted behavior in the event the I/O setup is not exact. Pedal Setup Parameters PEDAL1 TYPE - Chooses the type of pedal: continuous, momentary or latching. PEDAL2 TYPE - Chooses the type of pedal: continuous, momentary or latching. PRESET INCR - Chooses which pedal to use to increment the preset. When the selected pedal is depressed the next preset will be recalled. PRESET DECR - Chooses which pedal to use to decrement the preset. PRESET START/END - When using a footswitch to control preset increment/decrement the preset recalled will range between these values, wrapping around at the limits. For example if you wish to use a single footswitch to change presets you could plug it into PEDAL 2 and set PRESET INCR to PEDAL2. Each time you press the footswitch the preset will increment by one until the PRESET END value is exceed in which case it will jump to the PRESET START value. If you wish to cycle through presets 10 through 14 you would set PRESET START to 10 and PRESET END to 14.


PEDAL1 CAL - To calibrate a continuos pedal connected to PEDAL 1 press ENTER and move the pedal through its full range several times. Press ENTER again when finished.

PEDAL2 CAL - To calibrate a continuos pedal connected to PEDAL 2 press ENTER and move the pedal through its full range several times. Press ENTER again when finished.