Axe-FX Ultra System Exclusive Messages

for Axe-FX Ultra versions 10.02 to 10.05
(the same information for the Standard model can be found here)

Axe-FX parameters can be modified to control effects in real time, usually with a MIDI foot controller. For example, you can use a pedal to control volume or a wah effect. You can also send MIDI messages to Axe-FX external controllers to switch effect parameters, such as toggling between slow and fast rotary speeds. Most of the parameters you need to modify can be controlled in this way by attaching Axe-FX modifiers. All parameters can be controlled via system exclusive messages, but always use a modifier if possible. Default CC numbers for effect bypasses are shown here in the Default CC Number Table.

The purpose of this document is to make it easy to construct System Exclusive messages, for those who want full control over their Axe-FX. This information is not supported by Fractal. In fact, it's not even supported by the author! Data was extracted from XML configuration files used by the Axe-FX editor. Not all information appears to be used by the editor, so some data below, particularly value descriptions, may be misleading or incomplete. Nevertheless, I think it's easy to see what's intended and hopefully you won't have too much trouble building your own messages. Note that sending invalid or unintentional messages may have unpredictable results on your Axe-FX, so always backup and take care with your message data!

Overview

First of all, let's talk about hex. System exclusive data is usually shown in hex number format, where decimal numbers from 0 to 15 are represented by hex digits: 0, 1, 2, ... , 8, 9, A, B, C, D, E, F. They are also shown in hex pairs, such as 7F. To calculate the decimal value, multiply the first hex digit by 16 and add the second digit. So 7F is 7 x 16 + 15 = 127. Hex digits are shown in red in this document.

When you manually change an Axe-FX setting, you first select an effect block, then select a parameter, then set a value. This is exactly what the system exclusive message does, using ID numbers for the effect block, parameter, and its value. Messages that set an Axe-FX parameter value use this hex system exclusive format:

F0  00  01  74  01  02  0b  0b  0p  0p  0v  0v  01  F7

0b 0b is the block ID
0p 0p is the parameter ID
0v 0v is the parameter value

For example, to set a parameter value of 163:   163 / 16 = 10 with a remainder of 3, so the hex value is A3
Using the last hex digit first, 0v 0v is 03 0A.
Most values you need are shown in the tables below, and you can use the Hex Lookup Table at the bottom of this page to convert any decimal value to system exclusive hex values.

Other hex codes in the message are the Axe-FX device id, and I expect function codes to indicate that it is a parameter value message with an action of setting a value. All wrapped inside the start and end sysex bytes F0 ... F7.

Here's a complete example: Let's say we want to set the Compressor 2 Knee parameter to a value of 'SOFTER'
Compressor 2 block is 05 06, Knee parameter is 05 00 and SOFTER value is 02 00
So the full SysEx is:  F0  00  01  74  01  02  05  06  05  00  02  00  01  F7

Note that you should insert a pause between multiple system exclusive messages. Unfortunately, most foot controllers are not able to do this, so you may need to restrict yourself to one system exclusive per footswitch. I've found that a 100 mSec pause is reliable.

Contents

System Exclusive Tables