Firmware history

Axe-Fx Firmware Release Notes

Added "Crystal" pitch shifter mode. This mode allows longer splice times and other features such as reverse sampling and multiple feedback options. This mode is particularly suited to special effects. Also, an input gain control was added to allow swell effects, etc. Because of this any old presets that use the pitch block should be checked as the input gain will probably be set to less than 1. Adjust the gain if necessary and save the preset.

Enhanced capabilities of mixer block. The mixer block now provides pan controls and a stereo/mono switch. By using the mono mode and the pan controls, one can fade between two amps, for example, using the pan controls.

Added "Auto Delay Unbypass" feature. This feature, accessed from the Tempo menu, allows the user to automatically unbypass the delay and multitap delay blocks automatically whenever new tempo is received. The intended use is to recall a preset with the delay in a bypassed state. When a tempo is tapped in the delay block will go to the active state. For best results be sure to set the bypass mode of the delay block to "Mute In" to avoid glitching as the time is changed.

Version 1.32

NOTE: Many new features and parameters have been added for this revision. As such any presets saved under previous revisions may require some adjustments to be compatible with the new revision. Most importantly, the new Modifier parameters will need to be set for any presets that use Modifiers on their effect parameters. Only install this version when you have the time to go through your presets and adjust them accordingly. Also be aware that the bypass controller assignments may need to be updated. Although some tweaking is required to use this new revision we believe the extra functionality and new effects are worth the effort.

The two Quadtap blocks have been combined into one MultiDelay block with five sub-algorithms. See the manual for details. Any presets saved under earlier revisions that use Quadtap2 will lose that block under the new revision.

Related to the elimination of Quadtap2 the bypass controller assignments are shifted slightly. After upgrading to Rev 1.32 please check your bypass controller assignments under the I/O -> CTRL menu.

The Tremolo/Panner block has been upgraded to a true surround panner. See the manual for more details.

The Filter blocks now feature a right channel offset control. This allows setting different frequencies for the left and right channel but controlling both via a single modifier. Any presets saved under early revisions that use the Filter blocks should be checked for proper operation as the offset control will likely be set to 0.1. Set this to 1.0 to set the right frequency the same as the left. Be sure to save the preset after updating.

The Pitch block now has a Master Pitch control to allow controlling the pitch in real-time. The Master Pitch scales both pitches by the amount of the control. Any presets saved under previous revisions should be checked for proper operation as the Master Pitch control will likely be set to 0%. Set to 100% for normal operation. Be sure to save the preset after updating.

The Chorus and Flanger blocks now contain Phase Reversal switches for the right effect signal. When set to ON this increases the stereo image.

Added Sensitivity control to Envelope Follower. This control sets the threshold of the Envelope Follower. See manual for details.

The Modifier transforms now have Scale and Offset controls to allow easier and more flexible mapping to effect parameters. IMPORTANT: Any presets saved under previous revisions using modifiers will need to be updated since the Scale and Offset controls will likely be set to undesired values. For operation identical to the previous revisions simply set the Scale to 100% and Offset to 50%.

MIDI Clock synchronization is now supported. The Axe-Fx will lock on to a MIDI clock source and adjust its tempo to match.

All MIDI data is now buffered allowing for MIDI messages to be received during preset change. Previously any messages received during the preset change "blanking interval" were lost. The input buffer resolves this issue.

An issue with routing effects in the bottom row has been resolved.

Versions 2.xx

Version 2.00

New preset storage protocol introduced. This protocol allows many more parameters per preset thereby allowing for future expansion, new effects, new parameters etc. New firmware is backward compatible with presets saved with previous revisions.

Bug Fixes:

Reduced output level of panner by 6 dB to compensate for signal addition.

Fixed the depth of LFO2 only going to 0.5 at full depth.

New Features, Improvements, etc.:

Improved power amp simulation. Better negative feedback algorithm. This improves power amp phase response and feel. Frequency response is virtually unchanged but sounds better due to harmonic phase alignment. Touch response is improved and amp responds more to player "digging in" to the strings.

Added DEEP switch to power amp sim. When active this modifies negative feedback increasing low-frequency response.

The global LFO's themselves are now controllable. This allows attaching a controller to a controller. So now one can vary the LFO rate, for example, via an expression pedal or ADSR etc. Added monitor to envelope follower display. Added output gain control to follower to help compensate for long attack times.

Added "vibe" mode to phaser. Rotating order control fully CW engages this mode. The spacing of the poles is fixed in this mode and follows the old Univibe. The freq. span control has no function in this mode.

Added Dual Delay and Reverse types to delay block. The Dual type allows control over local and cross feedbacks as well as level and pan controls. Reorganized delay block GUI to be more intuitive.

Added Feedback Send and Return blocks.

Added second instance of Multi-Delay!!!

Improved fixed pitch shifting algorithms. Short splice times are now greatly improved. This affects both the pitch and multi-delay blocks.

Improved intelligent pitch-shifter algorithm ("note track" on or intelligent type), especially for shifts more than an octave.

Improved Plex-Shift decay time calculation so that actual decay time is closer to entered value. Added detune capability to Plex-Shift to allow fine pitch shifting.

Improved Plex-Detune algorithm. Also, delay time now compensates for splice time.

Added detune capability to intelligent shifter and crystals shifter.

Added Master Time to Multi-Delay block. Band-delay type now has LFO control of delay times.

Reduced CPU utilization for compressor when using soft-knee type.

Various optimizations have reduced overall CPU utilization slightly.

Added tuner offsets per string for custom temperaments.

Made the Sysex ID of the unit configurable. This allows setting the ID that the unit will respond to. NOTE: Upon firmware update this value will probably be zero. To insure compatability with any old Sysex data and the factory bank data you MUST set this value to 125.

Added full MIDI remote programming functionality. All aspects of the unit can now be remotely programmed using MIDI SysEx commands. Unit reports status back with SysEx messages.

Added preset backup/recall to/from FLASH capability. This allows saving first 64 presets to FLASH and recalling them in an emergency (someone monkeys with unit, dead battery, etc.).

The preset backup/recall feature applies only to the Standard unit. At the time, the Ultra did not exist and so it is not mentioned in the release notes. The Ultra uses this flash memory for other features that the Standard is unable to take advantage of due to processing power constraints.

Version 2.01 - 2.02 (Internal Releases)

Version 2.03

Bug Fixes:

Fixed mixer block mono/stereo mode select text not displayed.

Fixed Tremolo LFO type not sticking.

Features / Changes:

Reduced CPU utilization for null blocks.

Increased output gain of Spec. OD 2 model by 6 dB.

Improved Blackface model.

Added ducker to Delays. This is easier and works better than attaching the envelope follower to the mix or level controls. A "reverse" downward expander is used to reduce the wet signal level as a function of input level.

Added Boss SD-1 Distortion model.

Removed effect type blinking on effect recall function to aid readability.

Changed Chorus and Flanger "autodepth" from off|on to off|low|high. High gives twice the pitch shift as before. Low same as "on" was previously.

Added "Depth Range" paramter to delay blocks. Low same as before, high gives deeper pitch shift.

Rat and PI Fuzz models now have more input gain.

Added volume increment and decrement continuous controllers. Upon receipt of a CC message, volume is either incremented or decremented 1dB and preset is then immediately saved. This can be used to fine tune volumes between patches during performance.

Added makeup gain, detector type and contour controls to Compressor. Makeup gain switch compensates for threshold and ratio and keeps output level constant. Detector type switch selects between RMS (normal) and Peak modes. Contour control allows reducing amount of low-frequency content into detector thereby reducing pumping and squashing on certain types of source material.

Tuner display has added flat/sharp arrow indicators to aid in tuning from a distance.

Changed Phaser to automatically select "EXP" LFO type when selecting "vibe" mode.

Version 2.04 (Internal Release)

Version 2.05

Fixed Layout display not updating for MIDI remote place (for PC editor).

Fixed Control block not set properly for MIDI set (for PC editor).

Version 2.06

Added MIDI firmware version query function.

Fixed reverb crash when hicut freq less than locut.

Version 2.07

Added autoengage feature to wah.

Version 2.08

Added four new modes to Whammy.

Fixed some MIDI remote problems.

Removed wah autoengage and added to modifier parameters so any effect can be automatically engaged.

Version 2.09

Fixed can’t place shunt blocks via MIDI.

Added numeric readout to main level control in layout->mix page.

GUI now follows MIDI functions.

Version 2.10

Fixed Dual Delay times not being properly updated during preset recall if tempo true.

Added spring reverb algorithm.

Version 2.11

Fixed tuner crashing unit if activated by CC during preset change.

Versions 3.xx

Version 3.00

Fixed ping-pong delay 100% feedback not repeating forever.

Improved pitch detection routine.

Changed flanger feedback to -100% to +100%.

Added left feedback as master control in stereo delay.

Preset protocol changed to Rev. 3.0, compresses modifiers section.

Improved compressor by changing attack/release algorithm. Also decreased release time as it was a bit slow.

Added side-chain selection to compressor.

Added LFO target assignment to delay blocks.

Improved intelligent pitch-shifter.

Changed scale selection and added new scales.

Added "Global" amp feature allowing 10 global amps.

Version 3.01

Fixed glitching in pitch detector when tuner active.

Version 3.02

Fixed pitch detector crashing if large amounts of noise on input.

Version 3.03

Fixed compressor sidechain signal also in compressor input.

Fixed Presence Freq. parameter missing from Advanced Amp param list.

Removed large font to save data space. Replaced with double-size regular font.

Version 3.04

Fixed pitch detector semaphore problem.

Version 3.05

Fixed delay crashing if previous preset used reverse delay and current preset used something other than reverse and then changing to reverse.

Production release of Ultra firmware!!!!!!!!!!

Version 3.06

Fixed wrong labels on output mixer page for PAN3,4.

Version 3.07

Changed tap tempo to ignore taps very close together. This allows using the tap tempo feature with those MIDI controllers that send two messages per button press.

Version 3.08

Improved preset recall time.

Fixed delay block modifier indicators not scrolling with list.

Added output mixer to fx loop.

Fixed dumping single preset via MIDI corrupts config table.

Fixed dumping presets during high CPU use corrupts sent data.

Version 3.09

Fixed CC mapping for Ultra.

Fixed sidechain select for gate (Ultra).

Projects rebuilt using new (ver. 4.5) compiler.

*Note: FX Loop send page main mix bar now labeled Pan1. This is a typo that will be corrected in the next release.

Version 3.10

Fixed incorrect label on Main and FX loop output slider.

Version 3.11

Fixed Ringmod modifier icons.

Version 3.12

Improved preamp modeling. Tweaked several preamp models.

Version 3.13

Fixed Tempo knob in Pan/Tremolo.

Version 3.14

Fixed Ringmod modifier icons (again).

Version 3.15

Fixed PlexShift fuzzy if shift amount between 15 and 20.

Version 3.16

Fixed intelligent shifter not starting if shift exactly zero.

Version 3.17

Increased gain of Spec OD2 and Recto New amp models.

Increased gain of most drive models.

Added “Boost Switch” to amp block.

Pressing Enter with Drive selected toggles 12 dB input boost.

Bright Switch moved to Treble control.

Version 3.18

Returned stage 3 triode bias points to pre-3.12 values.

Fixed Ultra global scales starting at “C” instead of “A”.

Versions 4.xx

Version 4.00

This is a major release. There have been some significant changes and as such your presets may not function the same. Be sure to audition all your presets and adjust accordingly.

Added output level meters to status display.

Delay times are now entered directly rather than coarse / fine. Presets created with firmware prior to 4.00 will not have the same delay times and will need to be readjusted.

Dual-Delay type now has up to 8 seconds per delay-line.

If tempo is set times now read as the actual time in parentheses rather than just displaying “TEMPO”.

Changed Looper controls so that states are directly tied to CC value rather than toggling (except for ONCE control which toggles whenever CC message received as this allows rhythmic “stuttering”).

Output phase control for outputs (normal and 180 phase invert).

Auto-engage and bypass for modifiers. When ON, the target block will automatically be engaged when there is activity on the modifier. If the modifier value drops below 5% and remains there for a couple seconds the target block will automatically bypass.

Local bypass control. Modifiers may now be used to control the bypass state of a block. Press ENTER when the BYP MODE parameter is selected. If the value of the modifier is greater than 50% the block will be engaged, less than 50% and the block will be bypassed. This allows controlling the bypass state of a block using an External Controller (i.e. expression pedal or switch) rather than the global bypass CC’s.

System data dump and restore. All user data can now be dumped and restored via MIDI. Select “DUMP SYSTEM TO MIDI” in the utility menu to dump the data. Play the data back to MIDI IN to restore.

Input2 no longer has the noise gate applied to it. Previously the state of the main noise gate also controlled Input2. Now Input2 is always active. This prevents delay trails from being cutoff if the loop is after the delay block.

MUTE IN mode added to delay-based effects. This mode mutes all data into the block when the block is bypassed.

Added “HARD FUZZ” drive model. This is a hard-clipping 60’s-style fuzz.

Added LFO Run/Stop control. Select the TYPE parameter and press ENTER. If the value of the modifier is greater than 50% the LFO will run, otherwise it will stop.

Preset naming assistance. To ease entering a preset name, the PageL and PageR buttons can be used to set the character to a convenient starting point. Pressing these keys cycles through “ “, “0”, “A”, “N”, “a” and “n”. This reduces the amount of scrolling required.

Added “constant power mixer” to those blocks best suited. This preserves output level as the mix is changed.

Added User Cabinet IR support. Impulse Responses captured by the user may be loaded into the Axe-Fx non-volatile memory. A Window’s utility to convert wave files into the appropriate sysex file will be supplied.

Removed “1x8 BLUE" and "1x12 BLUE” cabinet types. These were very similar to the existing TWEED types. Replaced them with “4x12 GREEN” and “4x10 ALUM” (Bass cab) types.

Added “R121” and “D112” mic types. Added NULL type (no mic processing).

Added DRIVE parameter to cabinet blocks. This can be used to simulate speaker break-up.

Improved amp modeling and fixed Powerball model.

Added “HAD ODS”, “WRECKER”, “BRIT JM45” and “DAS METALL” amp models.

Fixed power-on recall of presets greater than 255.

Fixed power-on recall of certain non-volatile settings not being correctly loaded under certain circumstances (i.e. SYSEX ID).

Added Volume/Pan block to regular Axe-Fx. Added two extra blocks to Ultra.

Not mentioned in the official release notes, the Display Offset feature, optionally allowing presets to be numbered 1-384 instead of 0-383, was added in 4.00 and can be found in the Axe-Fx's I/O menu under the MIDI page

Version 4.01

Fixed Global Amps to be compatible with earlier firmware version.

Version 4.02

Fixed Dual Delay times not initializing correctly on preset recall.

Added “2x12 BLUE” cabinet model back in.

Version 4.03

Fixed LCD going blank on some units.

Version 4.04

Added WIDTH and LFO2 to Chorus. WIDTH offsets the delay times of the left and right. LFO2 modulates the LFO for voices 3,4,7 and 8 and can be used to create a lusher sound.

Fixed out-of-bounds indexing on chorus and amp blocks that could lead to crashes under unique circumstances.

Version 4.05

Added “Log A” and “Log B” taper types to Volume blocks.

Fixed Looper crashing when length of clip is max and reverse and once.

Fixed Ten-Tap echoes distorting if total delay time exactly equal to max.

Fixed LFO Tempo not being updated when new tempo entered.

Version 4.06

Fixed MIDI “Place Effect” remote command not placing some effects[Ultra].

Version 4.07

Fixed Multi-Delay feedbacks not being updated correctly upon recall in certain circumstances.

Added Diffusor type [Ultra] to Multi-Delay block for Ultra. This is comprised of four two-second allpass diffusers in series with control of time and feedback for each section. Master time and feedback controls are modifiable.

Version 4.08

Eliminated “zipper noise” when modulating Diffusor Master Time[Ultra].

Versions 5.xx

Version 5.00

Added passive tone control option to amp blocks. Global parameter allows choosing between active and passive as default when selecting amp type.

“Reference Class” pitch shifting including:

Improved intelligent pitch shifter, especially for large shifts.
Improved forward/reverse shifter used in Plex Detune, Plex Shift and Crystals algorithms.
Selectable in-block pitch detector allows for detecting pitch at block input giving far greater stability when using pitch feedback.
New hybrid time-domain/frequency-domain pitch detector in pitch block can track chords (Ultra only).
Pitch-tracking now compensates for shift amount resulting in more natural shifts.
Wider filter on pitched notes gives more bell-like and musical quality.
Adjustable low-pass filter.

NOTE: To compensate for the changes in the Crystals patches from pre-5.0 to 5.0, modify your existing patches:

Set MASTER FEEDBACK to 100%
Set SPLICE TIMEs to 50% of their original value
Set CROSSFADE between 50-100%
Increase MIX or LEVEL controls as needed

NOTE: To compensate for the changes in the Plex Shift patches from pre-5.0 to 5.0, modify your existing patches:

Set CROSSFADE between 50-100%
Set ...TIMEs to 50% of their original value

Fixed shared memory error between pitch blocks.

Added mono options to I/O. User can now select between stereo (default), L+R sum or copy left to right options.

Added many new possible tempos, i.e. 15/16, 1/64., etc.

Changed formant Q range from 2-20 to 4-40. This allows for a more intense effect. Existing presets will need to be auditioned due to range change.

Added filter type selection to outer bands on parametric EQ block. Choices are now shelving, peaking and blocking (i.e. highpass).

Fixed “WRECKER 1” model tone frequency. Originally it was incorrectly set at 200 Hz.

Fixed Powerball model. Schematic was intentionally incorrect leading to a myriad of improper values. Changed name to “ENERGYBALL”.

Added “PLEXI 2” amp model. Similar to original Plexi model but with different treble peaker on volume control and other minor changes.

Improved biquad and 1st-order filter performances. Results in smaller footprints and improved execution times.

Improved interpolation algorithm (Ultra only) used in chorus, flanger, and pitch blocks.

Improved allpass filter performance, gives slight improvement to phaser execution speed.

Reworked GUI code to improve effeciency and responsiveness, especially at high CPU loads.

Added RUN parameter to sequencer. This starts/stops sequencer. Parameter is modifiable. NOTE: parameter defaults to OFF and any old presets will need to be updated.

Added tempo controls to the Delay block LFOs.

Added “FET BOOST” type to Drive block.

Added “TAPE DIST” type to Drive block. This simulates distorion as would be encountered when overdriving a studio reel-to-reel tape recorder.

Reworked Drive block for better sound.

Added delay time parameters to Pitch block for Detune mode.

Added mod ability to dual delay times.

Version 5.01

Added modifier checking to delete bogus modifiers connected to illegal effects/parameters.

Changed preset recall routine to run faster and switch quieter.

Version 5.02

Fixed shunt not being placed when using editor.

Changed LCD update process to prevent command corruption.

Version 5.03

Fixed modifiers not being disconnected properly on patch recall.

Added input select to Amp block.

Decreased preset recall latency.

Version 5.04

Added code to ignore MIDI Active Sense messages.

Version 5.05

Fixed Multiband Compressor mute bypass mode not muting.

Mute output if exceeding CPU limit to prevent “stuck vector” squeal.

Added Master Pan parameter in Dual mode for Delay block.

Changed bypass control so that setting bypass state via MIDI operates the same as setting state via front panel. This will cause Edited LED to light and is considered normal operation.

Vectorized wet/dry values to eliminate chirping and volume surges when engaging/bypassing effects.

Totally reworked Drive block. Changed tone control to passive emulation. Updated/tweaked all models. Fixed mistakes in Big Muff Pi and Boss SD-1 models. Changed names of some models. Removed old Super OD model and replaced with new Boss SD-1 model. Put MXR Distoriton+ where old SD-1 model was.

Changed Drive block level control position to eliminate volume surges when engaging/bypassing.

Fixed clicking/popping on preset changes to presets using Multidelay block due to shared semaphore.

Fixed delay spilling over when delay spill off if delay time very long.

Changed Global EQ’s to 8-band Graphic. Moved phase controls to I/O menu. NOTE: If updating firmware the 8-band Graphic EQ’s will need to be set/updated (double-click BYPASS to zero all bands).

Fixed Autoengage incorrectly engaging blocks due to “leftover” data from previous preset.

Reworked Autoengage to operate better. Now engages at any point above 5%.

Fixed Pitch Shifter not shifting correctly for certain scales due to incorrect min/max shift limits. Fixed custom scales not loading right on preset recall due to scale being shared by both blocks and therefore being overwritten.

Fixed Harmonic Minor and Melodic Minor scale type labels swapped.

Added offset nulling to Amp and Drive blocks to reduce clicks and pops on preset changes.

Fixed Reset System Parameters not working due to SRAM lockout.

Added Global Option (I/O menu, MIDI tab) to ignore redundant MIDI program changes.

Version 5.06

Fixed loading single preset via MIDI hang.

Returned Autoengage to pre-5.05 operation and changed engage point to 20%.

Added Marshall Bluesbreaker and Shredmaster Drive models.

Version 5.07

Fixed CC bypass of effects not working properly if autoengage on and Ignore Redundant Program Change true.

Added MIDI bypass of Volume blocks. Volume1-4 now show up in I/O->MIDI menu and will likely need to be set/initialized. Wah1,2 controller numbers will also likely need to be reset.

Reduced autoengage point to 15%.

Version 5.08

Fixed Volume blocks taper not sticking.

Version 5.09

Improved power amp modeling by more accurately modeling high-frequency interaction with speaker impedance.

Version 5.10

Fixed Dual Delay pan values not “sticking”.

Added ducking capability to Multidelay block. Existing presets using the Multidelay will need to be auditioned. Turning “Ducker Atten” to 0.0 dB will defeat the ducker. Most, if not all, exisiting presets should have the attenuation set to 0 dB but you should check to be sure.

Added Gain control to Global Output EQ’s. This can be used to reduce/increase the overall level of all presets. When boosting bands on the Global EQ’s, output clipping can occur. This control allows you to compensate for this. The value of this parameter should be verified after installing the new firmware.

Fixed crash when using “Vintage” tone-stack due to arithmetic exception.

Version 5.11

Fixed 1x12 Thiele IR accidentally compiled into 1x6 Oval cabinet slot.

Fixed mild zipper noise in panner when using extreme widths/rates.

Added verfiy step to flash process. Added retry if verification fails. Unit now automatically reboots when flash is complete.

Added slightly more range to LCD contrast control.

Version 5.12

Fixed Bright, Deep, etc. “pull” switches not being saved when using Global amp.

Fixed Quad Chorus crashing if all rate multipliers at minimum and master rate very low.

Version 5.13

Fixed Ducker causing exception when Threshold at 0.0 (divide-by-zero).

Fixed Global Levels conflicting with MIDI map at 12 and 21. NOTE: you may need to reset your levels after update.

Version 5.14

Fixed verify on preset backup to flash incorrectly stating failed (standard only).

Version 5.15

Reprocessed all cabinet impulse responses to increase dynamic range. Reworked cabinet block to take advantage of increase.

Added 4x12 CALI cabinet model. Nice sample of a Mesa Traditional cab.

NOTE: The new cab will offset all user cabs by one, so update your presets accordingly

Version 5.16

Added diffuser to Quad-Tap algorithm. The diffusor is located at the input of the delay line. This can be used to smear the echoes. Diffusion sets the mix level and Diff Time sets the length of the diffusers.

Added code to defeat filtering in Delay block if Lowcut and Highcut are at their respective miminum and maximum values. This allows for infinite delays with no degradation.

Added ability to attach modifier to Drive block Drive control.

Added “Copy Out1 to Out2” feature. This parameter is located in the I/O->Audio menu. When set to ON the data at the main outputs (Output1) is copied to Output2 if the effects loop is not in use. The data at Output2 is affected by the Output2 Global EQ but not the Output1 Global EQ. This allows easily configuring a separate stage monitor and FOH send. Use Output1 to FOH and Output2 to stage monitor. If the effects loop is in use this parameter is ignored.

Fixed Mega-Tap time and level values being corrupted on edit/recall.

Fixed unequal L/R levels when Output1 mode set to SUM L+R.

Version 5.17

Fixed distortion in delay block if a very low value of modulation depth is being used.

Fixed vector corruption in Out1-to-Out2 copy feature when using certain routings.

Version 5.18

Fixed Global Mix parameter not working in Ringmod and Resonator blocks.

Fixed level of Output2 6 dB greater than Output1 when using Out1-to-Out2 copy and Out1 set to L+R sum.

Improved power amp modeling by improving speaker interaction model.

Version 5.19

Fixed vector being clobbered bug in Out1-to-Out2 copy feature.

Version 5.20 (Internal Release)

Improved Reverb algorithm by adding initial density control.

Version 5.21

Fixed value strings being overwritten by Delay block when modifier attached to certain parameters. This typically showed up in the Global Amp type being overwritten with a percent value.

Improved Reverse Delay algorithm. Doubled the available snippet length, changed crossfade method and improved overall performance and sound quality. Phase Reverse parameter now works as well. NOTE: Crossfade range has been changed from 1 to 255 ms. Audition existing presets.

Added modifiers to Dual Delay Left and Right level controls.

Added Mix control to compressor. For presets created prior to this release the mix value will be zero. You will need to adjust the mix to the desired amount and re-save the preset. Set to 100% for pre-5.21 sound.

Added Mix control to Drive block.

Added new tonestack placement option “END”. This places the tonestack after the power amp simulation.

Added Warmth parameter to Power Amp simulation. This parameter can be found in the Advanced menu and controls the power tube and transformer interaction. Set to zero for pre-5.21 sound. Increasing this value increases the apparent warmth and depth of the tone, especially as the power amp is driven harder. This parameter defaults to a non-zero value whenever a new amp type is chosen.

Fixed bug in Whammy where pitch would be stuck. Only affected standard models.

Version 5.22

Changed Delay block algorithm to eliminate zippering on tempo changes. Reworked modulation for better sound quality.

Version 5.23

NOTE: Support for presets created with Version 3.xx or earlier firmware has been dropped. If you are upgrading from Version 3.xx or earlier, upgrade to 5.22 first and run the “Update All Presets” utility in the Utility->Preset menu.

Changed range of frequencies on Resonator block to allow more varied tones. Audition any existing presets that use the Resonator block.

Added Mono|Stereo input select to Resonator block. In Mono mode (default) left and right are summed and fed to all four resonators. In stereo mode the left intput is fed to the first two resonators and the right is fed to the last two.

Improved preset change behavior to reduce pops and clicks.

Version 5.24

Fixed some knob positions not set properly when modified in Drive, Format, Synth and Quad-Chorus blocks.

Version 5.25

Fixed MultiDelay block crashing on modifying Master Q.

Improved preset switching speed.

Version 5.26

Fixed popping on preset change when using volume block.

Versions 6.xx

Version 6.00

NOTE: THIS IS A MAJOR RELEASE. YOUR PRESETS MAY SOUND DIFFERENT. AUDITIONING YOUR PRESETS IS HIGHLY RECOMMENDED.

Added the following cabinet models:
- 1x12 E12L: Based on EV 12L 1x12
- 1x12 STUDIO: Based on Mesa Studio 22 1x12
- 1x12 OPEN: Based on open-back Eminence 1x12
- 1x12 BLUES: Based on open-back Fender 1x12
- 1x15 BLUES: Based on Peavey Delta Blues 1x15
- 2x12 BOUTIQ: Based on Matchless 2x12
- 2x12 GOLD: Based on Celestion Gold 2x12
- 2x12 G12H: Based on Celestion G12H 2x12
- 4x12 RECTO: New IR from Mesa Oversized 4x12
- 4x12 V30: Based on Framus 4x12
- 4x12 T75: Based on Marshall 4x12
- 4x12 GERMAN: Based on Bogner 4x12
- 4x12 METAL: Based on Engl 4x12
- 4x12 JM2000: Based on Marshall JCM200 4x12
- 4x12 SOUTH: Based on Peavey 6505 4x12
- 8x10 BASS: Based on Ampeg SVT 8x10
- 1x15 BASS: Based on SWR 1x15

Reprocessed all cabinet IR’s to 1024 samples. Cabinet block can now be run in three modes:
- MONO HIRES: Mono 1024 sample convolution
- MONO LORES: Mono 512 sample convolution
- STEREO: Stereo 512 sample convolution

Mono Lores can be used to decrease CPU requirements as processing load will be cut roughly in half.

NOTE: Any presets using user cabs will be affected. The cabinet type will be incorrect and require adjustment. Also, user cabs will need to be reprocessed and reloaded to support the new IR length.

Additionally, any presets created with pre-6.00 may sound different because of the Mode select on the cab block. Since that parameter didn't exist before it will have an indeterminate state. Set to Stereo to restore the preset's original tone.[1]

To load user cabs now the location is determined by the selected user cab in Cabinet1 block. To load an IR into a user location select the desired user cab location, i.e. “USER 2” and then send the sysex file. The IR will load into the USER 2 cabinet location.

Reworked several amp models slightly. Adjusted final output gain.

Added “Thump” modeling to power amp simulation. This models the output transformer interaction with the speaker impedance. The amount of thump is adjustable from 0 – 10. Value is set to a default value when amp type is selected. When using a tube power amp you may want to set this to zero as the tube power amp will produce it’s own thump. To facilitate this the global power amp bypass has an additional mode that deactivates the thump modeling.

Reworked Hiwatt (HIPOWER) models. Refined cathode cap values, tone stack and tone stack placement. Be sure to reselect amp type to load new values.

Added new tone stack position: MIDDLE. This places tone stack midway between gain stages.

Added bass amp model SV BASS. Modeled after Ampeg SVT.

Added Slew Rate limiting modeling to drive block. This models the slew rate limiting produced by early op-amps. Increasing the SLEW LIMIT parameter limits the large signal frequency response of the virtual op-amp. Adjust to taste. Set to zero to deactivate.

Added 2^nd-order mode to phaser.

Added “Pedal Style” compressor. The compressor now has a new pedal-style compressor based on feedback topology. Set the type to “Pedal” to select (set to “Studio” for the original compressor algorithm). This type is more responsive and may be more suited to certain guitar styles.

Fixed compressor CPU load changing when activated vs. bypassed.

Version 6.01

Reordered cabinets to group like types together. Old presets are automatically parsed and converted on recall, no need to manually update.

Fixed incorrect bass cap and pot taper in Energyball tone-stack.

Fixed compressor input filter not working.

Fixed compressor soft-knee mode not soft. Reworked soft-knee algorithm. There are now three soft knees to choose from: soft, softer and softest. The knee transition region is 5, 10 and 20 dB respectively.

Tweaked code to reduce CPU utilization slightly.

Removed MIDDLE tone-stack position. PRE now automatically puts the tone-stack in the appropriate position for the selected amp model.

Accidentally left out of the official release notes, "there's now a quick-edit feature. If you're in the Layout->Edit menu and you've selected an effect pressing EXIT does a quick jump to a shunt. If the block is a shunt pressing EXIT does a quick jump to none."[2]

External Links

G66.eu article: "AXE-CEPTIONAL (Firmware mutations on the Axe-Fx)"