Always consult the Owners Manuals and FAQs first.
FM3 information is being added as it becomes available, but it's preliminary and not final until release

Axe-Fx III processor

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Forum discussions:


Pictures of Axe-Fx III rigs

Owners of an Axe-Fx III proudly show their rigs

About the Axe-Fx III


"It's a new platform. It will grow over time. It was time for an updated platform. TigerSHARCs are discontinued, the interface was dated, etc. The III is what the II would be if we could've upgraded the hardware via a firmware update." source
"Remember it's a lot of work migrating stuff to a new architecture. The III is a brand-new platform. Just as the II had dozens of firmware update the III will receive many updates and there's so much power there that we can improve everything over time." source
"The Axe-Fx III was designed so that single preset can be thought of as an entire rack full of processors. Each virtual processor has up to four presets. So if you were trying to do spillover in a rack you would use two reverb processors." source
"These Keystone processors chew through data like a hot chainsaw through a sorority girl. The Axe-Fx III is a beast. I don't think people realize how powerful it is. It has the equivalent power of 8 SHARC chips, at least. And that's just the DSP. The memory bus is 3-4 times faster than other stuff." source
"The only product more transparent than the FX-8 is the Axe-Fx III." source
"The Axe-Fx III, FM3 and the other products in development all use the "Ares" architecture. This is a portable client-server architecture that allows easy porting of effects and models between hardware platforms. When we ported the Axe-Fx III models to the FM3 it involved nothing more than copying the file. We created the Ares architecture three years ago and all new products use it. It's a comprehensive hardware and software paradigm that allows any number of clients to communicate with a DSP server. The architecture supports multiple DSP cores. Clients can be located on the same core, a different core on the same IC, a different IC on the same board or on completely different hardware, i.e. an editor running on a PC or a foot controller. For example on the FM3 the UI is a client running on the ARM core. The Ares architecture is even processor agnostic. The Axe-Fx III uses TI DSPs while the FM3 uses Analog Devices. The Ares architecture was a huge undertaking with the ultimate goal of faster product development and easy synchronization of multiple product lines. It allows me to work on algorithms and new models and the engineers can then easily port those to the other products." source


Dimensions and weight:

  • Width: 19.00" (482.60 mm)
  • Height: 5.16" (131.10 mm). That's 3U
  • Depth:
    • 11.530" (292.87 mm) including front handles and rear jacks.
    • from the faceplate to the rear jacks: just under 10" from the mounting face of the faceplate to the edge of the jacks. source
  • Weight: 15 lbs 2.4 oz (6.87 kg)
"Large screen meant we had to make it 3U. But it's much shallower than the II." source


  • Two 1.0 GHz floating-point “Keystone” DSPs (2.8 times faster than the TigerSHARC DSPs in the Axe-Fx II)
  • Video display processor
  • 500 MHz 16-core XMOS USB microcontroller:
    • Supports 8x8 audio at 48kHz, 24-bits
    • MIDI-Over-USB is about 10x faster than an Axe-Fx II


  • PC1600 DDR3 memory
  • Hundreds of MB of FLASH memory
  • Enough non-volatile memory for over 4000 IRs

LCD display:

  • Custom-design full-color 800x480 TFT display
  • Specifically designed to provide animation
  • The backlight intensity is not adjustable.
"You can turn it down but you can't turn it off. There is no danger of burn-in as it's an LCD not an OLED." source

The third "I" in the logo may appear less bright than the other characters when viewed from an angle. Nothing to worry about!

Analog I/O:

  • Audiophile-quality components

Backup battery:

  • CR-2032
"You can install the battery yourself. It's a standard CR2032 motherboard battery." source


  • 20 dBu maximum


(about fan noise) "Actually the problem was the lock nuts were too tight. The fan is mounted on rubber bushings but the nuts were too tight compressing the bushings." source


There's no harm in leaving the processor turned on all the time. source

There is power transient suppression circuitry, so that the Axe-Fx III won't make any loud pops when powering on/off.

"There is a voltage monitor that reboots in the event the voltage drops below a certain threshold." source
"The III has power on/off detection circuitry that mutes the outputs when it detects a power transient." source

The Axe-Fx III has a universal power supply. Power consumption is less than 40 watts.

When powering on, the III displays diagnostic messages during the first phase of the boot routine.

This includes "checking mailbox":

"Going all the way back to the original Axe-Fx I used a concept called a "Mailbox" to communicate between processors. Each processor has an inbox and an outbox. I'm self-taught in programming and computer science so it was just a way I came up with to send data back and forth. Turns out that mailboxes are actually a technique used in interprocessor communications. In this specific case the processor is checking the mailbox from the front panel to see if any buttons were pressed at power-on." source
"To reduce boot time some of the boot tasks (copying presets and cabs from slow FLASH memory to fast DDR memory) are done in the background. This takes a couple minutes to complete and reduces CPU power available to servicing other low-priority tasks. Once the tasks are completed any lag will go away." source

More information about I/O


Product information:

"The audiophile-quality signal path features Burr-Brown SoundPlus and Analog Devices op amps, PPS film caps, a high-voltage bipolar power supply for low distortion and maximum headroom, and flagship-quality Cirrus Logic converters with fully differential input and output circuitry. A thoughtfully designed multi-layer circuit board features gold plating and extensive ground fill for low EMI and immunity to interference. This impressive level of engineering yields the most pristine sound quality, lowest THD, and lowest noise floor of any product we’ve ever created—by far."

"All knobs and buttons are backed by professional grade components with life expectancies in the millions."

"Internally, the unit features a DSP module that is made in the USA and mechanical design guided by years of experience designing dependable rackmount units for touring musicians."


"It was a monumental amount of work. The DSP board design was the most difficult hardware design we've ever done. It's a 10-layer board with all fine-pitch technology. Then migrating all the algorithms to a new processor architecture. The team did a phenomenal job." source
"The chassis and some of the boards are made in China. The DSP module is made in Merrimack NH, USA." source
"Roughly 50% (by cost) of the Axe-Fx III is made in USA. The chassis and simpler circuit boards are made in China. The DSP module is made right here in NH. source
"The Axe-Fx III is about 50% domestic content. source
"The front panel around the buttons is steel and covered with a polycarbonate overlay. The bezel is anodized aluminum." source
(about heat) "Less than an Axe-Fx II." source
"Designing a product is all about compromises. Do you want a phantom power mic input? Well that costs money. So either you have to raise the price of the product or cut costs somewhere else. For something that only a small percentage of people will use. Since we target the pro market our customers will likely use their own mic pre's like a Neve or API. So we don't include it and don't have to cut costs on other things." source
"The Axe-Fx III is assembled, programmed, inspected, and tested at our facility in New Hampshire." source
"FWIW the backlight in the Axe-Fx III is not PWM. I had the OEM change it to a circuit I designed. I eliminated PWM sources inside the unit wherever possible so as to keep EMI to a minimum." source
"In general I overdesign things. I.e. if a capacitor is used to filter a 5V rail most designers will spec a 6.3V part. I'll spec a 10V part. For electrolytic caps I always spec long-life and high-temperature parts. We always use ENIG (electroless nickel immersion gold) circuit boards with FR-4 cores, no phenolic crap or HASL." source
"The glue is just to keep the switch from sliding around in the opening. It's a snap-in type like many products use now. You may have noticed those types tend to slide around a bit in the opening. So we put a little glue on there to make it more secure. It's unnecessary and an extra manufacturing step but makes the switch feel better. The Axe-Fx III does not make any compromises. Every part used is high quality. The converters are Cirrus' highest performance models. The capacitors are high-temperature, low-impedance, long-life parts (Panasonic FK series, look 'em up). The power supply costs closer to $27. The DSP module alone costs close to $250. The analog paths use premium op-amps, not the cheap TL07x and NE553x used in most other products." source

Read this post about the parts and manufacturing

More pictures of the circuit board

III circuit.jpg

Model differences

(June 2019) "The newer units have a temperature sensor IC on the mainboard. The original units do not have this." source


(latency) "It's the equivalent of 15 inches. Most modeling products have latencies in the range of 1-2 ms which is roughly equivalent to 1-2 feet away from the speaker. Our products have less latency than most, if not all, competing products as that was a design goal from day one. The equation is ~1 ft per millisecond of latency." source
(comparing to the Axe-Fx II XL+)
"It actually does sound a little better. The extra DSP horsepower means that we didn't have to make compromises in some of the algorithms. The amp modeling algorithm is very similar but there's a few places on the II where we had to make compromises to get the algorithm to run within the allotted time. Also the III has a higher internal oversampling rate and a higher bit depth on some calculations (64-bit vs. 40-bit)." source
"The converters are the limiting factor. It's already way faster than anything else." source
"The digital signal is 32 bits." source
"The Axe-Fx III uses 32-bit floating point." source
"32 bit floating point mostly. 64 bit floating point in critical locations in the amp block." source
"64-bit processing is used in critical locations to minimize coefficient sensitivity." source
Iii Benchmarks.jpg

Tests of aliasing performance

Comparing the Axe-Fx III

Axe-Edit III


Read this: Editors



Read this:

The "DSP" firmware provides all the models and features. This firmware is frequently updated.

There's separate firmware for the USB subsystem of the Axe-Fx III. This needs to be updated only when Fractal Audio says so.

The features of the FC controllers are included in the DSP firmware. But there's also separate low-level firmware for the FC controllers. Again, this only needs to be updated when Fractal Audio says so.

I/O connections


Read this:

Pedal ports

The Axe-Fx III has two pedal ports for direct connecting to expression pedals and/or external switches.

An expression pedal should have a linear resistance taper, max resistance of 10-100 kOhm, and requires a TRS-to-TRS cable. The pedal must be calibrated before use in the I/O menu.

An external switch can be a momentary or latching one, and uses a TS-to-TS cable. Use the I/O menu to tell the hardware what type of external switch you're connecting, and to calibrate connected pedals.

The Owner's Manual contains tutorials about connecting, calibrating and configuring a pedal, either connected directly to the device, or via another controller.

Unlike the previous hardware generation of hardware, the Axe-Fx III allows selecting a pedal or switch directly as a modifier source (without assigning it to an external controller first).

The FC-6 and FC-12 foot controllers also allow connecting expression pedals and switches to the controller. These are configured in the Setup > Foot Controllers menu. Read this: FC-6 and FC-12 foot controllers


Number of presets:

  • 512
(Axe-Fx III) "The hardware is not capable of supporting more presets." source
(Axe-Fx III) "If you want more preset space you would have to sacrifice user IR space. Each preset uses the equivalent of two user IRs. There are three FLASH chips on the DSP module: one for presets, one for factory IRs and one for user IRs." source

About the factory presets:

Effects list

Click on the image below:

Iii all-blocks-3x13.jpg

System reset

Read this: Reset system parameters

Buttons, knobs, switches


Navigate and operate

  • VALUE wheel, with push-button function (which can be disabled in Setup > Global)
  • NAV buttons. On the Home page these let you switch presets (left/right) and scenes (up/down)
  • PAGE LEFT/RIGHT buttons
  • HOME menu button
  • EDIT button
  • ENTER/EXIT buttons. ENTER also jumps to the layout grid from any screen
  • 5 rotary push-buttons (ABCDE) perform various functions in the GUI
  • Output level knobs for the 4 outputs
(assigning soft knobs to amp controls) "That is the plan but we haven't implemented it yet. The hooks are all there in the firmware. The idea is a "Performance" page where you select up to 10 global parameters that you can adjust at any time." source



  • The PERFORM screens on the Axe-Fx III allows fast access to max 10 often-used parameters. You can select these in Axe-Edit III in the Perform screen. You can use block parameters, parameters from controllers (including Tempo), global parameters). There's a Global Perform screen and a Per-Preset Perform screen.
  • Soft-knobs D resp. E let you jump to the Edit menu of AMP 1 resp. AMP 2

VALUE wheel:

  • Press to switch to the layout grid (unless disabled in the Setup menu). Press HOME or another button (not EXIT) to leave the layout screen

HOME page:

  • Press ENTER to jump to the layout grid. Press EXIT to return to the Home screen
  • Use NAV UP/DOWN to switch scenes
  • Turn knob "A" to switch scenes
  • Use NAV LEFT/RIGHT to switch presets
  • Page to the Global Perform screen and Per-Preset Perform screens and push the soft-knobs D resp. E to jump to the Edit menu of AMP 1 resp. AMP 2
  • Press Edit to open the Edit menu of the currently selected block (not visible)

AMP block > Output EQ:

  • Press ENTER to flatten all bands, and NAV UP/DOWN to change bands
  • Press NAV UP/DOPWN to change the EQ type


  • Press-and-hold ENTER to create (or clear) a series of shunts
  • Page to the TOOLS menu, and use the Value wheel or soft-knob A to select a function: move or copy rows/columns, copy a channel, copy a scene, manage Global Blocks
  • Press ZOOM to view the preset's VU meters (reference for setting preset levels)

Block Edit menu:

  • Press EDIT again to advance to the next block in the preset (top-to-bottom, left-to-right)


  • Press EDIT after storing a preset to go right back to where you were


  • Press TEMPO to open the Controllers menu


  • Press ENTER to randomize

Switch presets

To switch presets:

  • Value wheel or NAV right/left button
  • Foot controller
  • MIDI
  • Editor

More about Presets

Switch scenes

To switch scenes:

  • NAV buttons or soft knob
  • Foot controller
  • MIDI
  • Editor

More about Scenes

Switch channels

To switch scenes:

  • Soft knob
  • Foot controller
  • MIDI
  • Editor

Read this: Channels

Control Switches

Read this: Modifiers, Controllers and Control Switches

Remote control

FC-6 and FC-12 controllers


Read this: FC-6 and FC-12 foot controllers



Using other MIDI controllers:

Read this: MIDI

Tips and tricks

Migrating from Axe-Fx II to Axe-Fx III

Read this: Comparing the Axe-Fx III to the Axe-Fx II

Use FracTool to transfer your Axe-Fx II presets.

Help, no sound


Read this: Troubleshooting