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Looper block

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Available on which products

  • Axe-Fx III, FM9 and FM3: 1 block
  • Axe-Fx II, AX8 and FX8: 1 instance

Channels or X/Y

The Looper doesn't support X/Y switching or channels.

About the Looper block

On the FM3, AX8 and Axe-Fx series, the Looper is a dedicated effect block, providing minutes of stereo or mono loop time. The FM3, FM9 or FC-6/FC-12 provide dedicated Looper controls.

On the Axe-Fx III, the Looper provides more than 5 minutes of stereo looping time.

The Looper block on the FM3 and FM9 is the same as on the Axe-Fx III, with 120 seconds of looping time.

On the FX8, the Looper is a global feature, which position is customizable.

Wikipedia's Loop (music) article has more information.


[1] We completely rewrote the Looper. Over five minutes of stereo recording with undo.

[2] Loopers have unique hardware requirements, i.e. lots of memory. General-purpose guitar processors like the Axe-Fx don't need the amounts of memory that loopers require and adding that memory for a single effect would increase costs, probably considerably. Furthermore the processors used in products like the Axe-Fx are limited in the amount of memory they can address. The DSP used in the Axe-Fx III is the most powerful commercial DSP available but it's still limited in its memory address space.

Also, most loopers trade off bit-depth and sample rate for loop time.

Therefore you're unlikely to ever find a multi-effect that has the loop time and features as a dedicated looper.

If I were to make a dedicated looper I probably wouldn't use a DSP but something like an ARM with a lot of external address space. There isn't really much audio processing required, it's mostly memory access.

Position of the Looper block on the grid

If the Looper block is placed before the Amp block, changing amp models will change the sound while the loop is running.

If the Looper block is placed after the Amp block, changing amp models will NOT change the sound while the loop is running.

Legacy devices

Axe-Fx II

Mono — 60 seconds

Stereo — 30 seconds

Mono with Undo — 30 seconds

Stereo with Undo — 15 seconds


Mono — 4 minutes

Stereo — 2 minutes

Mono with Undo — 2 minutes

Stereo with Undo — 1 minutes

Looper Control Mode is accessed using a F-switch.


The Looper in the FX8 has additional features. It's a global looper so it's always present, in every preset. It can be positioned in different locations. It can be disabled, which decreases CPU usage.

Mono— 8 minutes

Stereo — 4 minutes

Mono with Undo — 4 minutes

Stereo with Undo — 2 minutes


  • IN PRE

The location can be set in the Global Settings menu and can be overridden per preset.

If you can't hear the Looper, check the LOOPER LOCATION. It must not be set to NO LOOPER. If it is set to GLOBAL, check the GLOBAL LOOPER LOCATION in the Global Settings menu to ensure that it is not set to NO LOOPER. This may also be due to PRE/POST settings. If your rig uses only the PRE chain or only the POST chain, set LOOPER LOCATION accordingly.


Max Loop Time

This sets the maximum recording time. It allows a loop to be automatically created once the loop time exceeds this value.

If recording and time reaches the maximum recording time the mode changes to that specified by Record 2nd Press, only on the first pass of a new recording.

(Record) Threshold

If enabled, recording will not start until the input level passes the specified threshold, set by the Threshold parameter. If you press Record, you will see the indicator come on and then turn off. This means it is waiting for input to start recording. Once you start playing you'll see the indicator come on and you are recording.

Axe-Fx III, FM9 and FM3 – Use the soft knob or main Value knob to adjust the threshold value, or use the Record Threshold parameter on the Config page. When set to a value greater than -80 dB recording will not start until the input signal exceeds the set value. The Record icon will blink when the Looper is armed for recording and will turn solid when recording starts. The meter at the bottom of the page can be used to help set the Threshold. Use the soft knob or main Value knob to adjust the threshold value or use the Record Threshold parameter on the Config page.


When set to ON, the loop fades out/in at the end/start of the loop.


Start recording or enables overdubbing. There's no separate Overdub control on the Axe-Fx III, FM3 and FM9.

What happens when you press Record a second time is user-definable, see below.

Record 2nd Press

Axe-Fx III, FM9 and FM3 only.

The choices are:

The second press ends the loop and enters Overdub mode.
The second press ends the loop and enters Play mode.
The second press ends the loop.

Trim Start, Trim End

These are available on the Axe-Fx III, FM9, FM3 and AX8 only.

Use these to adjust the start and end points of the loop. The graph on the Control page provides visualization of the loop and the start/end points.


Quantize will automatically trim your recording to the nearest beat and is recommended to be used in conjunction with Threshold.

To use: Press Record, then start playing on a downbeat click. Press Record again to stop.

If you stop slightly too soon or too late it will automatically trim the recording to the length. Also, it will automatically start playback on the downbeat, so if you stop playback and start it up again later, it should always come back in on the beat.


  • When recording, this operates as Undo, removing the last recorded stack layer.
  • When playing the loop, this enables or disables the last Undo operation. Subsequent presses toggle the layer on and off.
  • When looping is stopped this changes into Erase, completely erasing the recorded loop.

Undo/Erase requires CPU cycles briefly. When used with presets with high CPU utilization this can result in warnings or audible pops.

(Half) Speed

When Speed is set to HALF, the virtual tape runs at half the normal speed. The speed can be also be toggled via a MIDI CC message.

Remote control


The FM3 and FM9 allow the onboard switches to be assigned to Looper functionality, or you can assign these to a connected FC controller.

FC-6 and FC-12 controllers

The FC controllers let you operate the Looper.

Foot switches

Assign the Looper controls, such as Play and Record, to external switches for remote control. Some functionality requires a latching switch, for other stuff a momentary switch is required.

You can also assign Looper Record/Play to an external switch, for easy access at all times.

If you use a controller with Tap and Hold functions, be aware that the function triggers on the upstroke of the switch, not the down. To avoid this, don't assign a HOLD function to the RECORD and PLAY switches. Alternately, set Looper Record second Tap to PLAY and use that to end your recordings.


The Axe-Fx II uses these MIDI CCs for remote control.

  • Record: 28
  • Play: 29
  • Once: 30
  • Dub: 31
  • Rev: 32
  • Bypass: 33
  • Half: 120
  • Undo: 121

The Axe-Fx III, FM9 and FM3 let you map MIDI commands to the Looper in the MIDI/Remote menu.

MFC-101 Looper Control Mode

The MFC-101 MIDI foot controller has a Looper Control Mode. This mode is enabled by pressing and holding the Reveal switch. The MFC-101 will display "LOOPER CONTROL MODE" for two seconds and the red LED will be lit on the Reveal switch. This mode is disabled by selecting the Reveal switch. In Edit > Setup you can select if this requires short or long pressing-and-holding. You can also disable Looper Control Mode altogether.

MFC-101 Looper Control Mode Mini Manual


FX8 and AX8

The AX and FX8 allow the onboard switches to be assigned to Looper functionality.

Tips, tricks and troubleshooting

No Global blocks

The Looper block doesn't support Global blocks.

No delay when pressing Record

Switches on the FM3, FM9 and FC controllers that have a secondary HOLD function, typically engage on the "release" action, instead of on the "press" action. This can cause an undesired delay when operating the looper, especially when pressing the Record switch. Solve this by disabling the HOLD function of the switch.

Use the Looper for sound tweaking

The Looper is an excellent tool for tweaking sounds. Place it before before the Amp block, and record a loop. Now keep playing it back while you adjust amp settings, change the cab, adjust effects etc. You'll hear the differences in real time.

Or use it to compare two sounds. Place it after the Amp block and record. Start tweaking. When you want to hear the original tone, play back the sample.

No gap when switching presets

The loop buffer will be erased when switching presets, unless Spillover is enabled in the Global Settings menu. To survive preset switching, both presets must contain the Looper, set to the same mode.

Route the Looper output

The Output blocks and effects loops on the Axe-Fx III, FM9 and FM3 make it easy to send the signal coming from the Looper to a specific output for further processing and routing.

Use the Looper for a soundcheck

Record a loop and press Play. Now get off the stage, walk around the venue and listen.