ML:2 Documentation

Quick Start

ML:2 includes a ribbon power cable and nylon M3 screws

Installing Your Module

  1. Power off your eurorack system.
  2. Plug in the power supply ribbon cable from the ML:2 to your system’s power. Circuit Happy follows the quasi-standard of Red Stripe Down. The red stripe indicates the -12 V power bus. Make sure that the ribbon cable’s red stripe is aligned to the bottom edge of the ML:2 circuit board and is connected to -12 Volt bus of your system’s power supply.
  3. ML:2 includes two nylon M3 screws to secure the module to your system’s mounting rails.
  4. After ML:2 is correctly plugged in to power and screwed in to your case, power on your system to boot up ML:2!
The exact name of the network is included in the Quick Start card and is also affixed to the module itself

Connecting To Your ML:2

When ML:2 boots up, it will automatically go in to Access Point Mode. The WiFi light will slowly pulse to indicate this mode.

In Access Point Mode, ML:2 creates its own WiFi network. Connect your computer or mobile device to this WiFi network. The name of the network is included on the back of the Quick Start card included in the ML:2 box.

The network name looks something like this:

The default password is:

Configuring ML:2 with the Control Panel

ML:2 hosts a web site for configuring its settings. The URL is based on the same name as used in the Access Point WiFi network.

The URL looks something like this:
(bold text is the same name used in WiFi network)

After the Control Panel loads, a message should greet you and guide you through the rest of the setup process.

The WiFi light will glow a solid color when it has successfully connected to your local WiFi network. If it failed to connect, it will go back in to Access Point Mode.

If the ml2-xxxx.local URL does not work

If you are connected to the ML:2’s WiFi network and you are not able to connect to the “.local” web address then your mobile or desktop computer may not support mDNS. This is required to allow the “.local” address to work.

Try entering this IP address instead:

Output A is generating a clock signal for a sequencer module and Output B is triggering a reset to the Reset input of the sequencer at the start of each loop.

Connect ML:2 to Your Modules

The A and B Outputs

ML:2 has two outputs, A and B. The outputs can be configured to generate clock, loop reset trigger, or a high gate while the clock is playing.

The factory default settings for the two outputs are as follows:

  • A: 4 PPQN clock
  • B: Loop Reset Trigger

Plug Output A in to the Clock/Sync Input on the module you wish to synchronize with ML:2. Plug Output B in to the Reset Input, if your module has one.

When you press the Play button on ML:2 it will start generating a clock signal on Output A. Output B will create a trigger at the start of each loop. The lights in the four buttons will cycle from top to bottom showing you the phase, or position, of your loop.

You may have to change the settings of Output A and B to match the module you wish to synchronize. Click here to learn more about the Output Settings.

The Control Panel

Since the interface of ML:2 is so minimal, there are many settings that can not be easily accessible via the front panel. The ML:2 instead hosts an interface to access these settings called the Control Panel. In the Control Panel you will find settings for storing and editing WiFi networks, performing firmware updates, and changing the playback behavior of the A and B outputs.

Connecting to the Control Panel

If ML:2 is in Access Point Mode, then connect your computer or mobile device to ML:2’s WiFi access point. The name of the default name of the network is printed below the serial number on the label attached to your ML:2’s main circuit board. The name and serial number are also included in the Quick Start card included in the box with your ML:2.

If your ML:2 is connected to your local WiFi network then connect your computer or mobile device to the same local WiFi network.

Connecting via the “.local” URL

Now that your computer or mobile device is on the same network as your ML:2 you can access the control panel by opening a web browser and entering the following URL based on your Missing Link serial number:


The exact name is included next to your serial number on the quick start card or on ML:2’s main circuit board. Also note that there’s a trailing “/” at the end of the URL. Some browsers need this forward slash in order to correctly parse the URL.

Connecting via an IP address

If your Windows computer or mobile device does not support Multicast DNS (aka Apple Bonjour) you will not be able to access ML:2 via its “.local” web address. Apple has a Windows installer for mDNS/Bonjour support. If you cannot install mDNS services then you will have to access your Missing Link via its IP Address.

ML:2 IP address when in Access Point Mode

The IP address to access your ML:2 Control Panel is:

ML:2 IP address when connected to your own WiFi network

The IP address is not known when it is connected to your own WiFi network since the address will by dynamically assigned by your WiFi router. If you need to connect via IP address then you should configure your WiFi router to give your ML:2 a dedicated IP address. You can do this with most routers via the router’s administration app or web page.

Output and Playback Settings

The Playback and Output Settings reside at the top of the Home page for the Control Panel.

Playback Settings

At the top are the Playback Settings. This includes a Play/Stop button, Start/Stop Sync switch, Tempo, Loop Size, and Offset controls.

Start/Stop Sync

When this feature is enabled The Missing Link will listen for Start/Stop transport messages from any other Link 3.0 peers with Sync Start/Stop enabled. If any of the devices start playing or stop playing the other devices will also start or stop playing.

Tempo (BPM)

The tempo controls how fast everything plays. Tempo is set in Beats Per Minute. Changing this value will also change the Tempo of any other Link devices you are networked with.

You may either enter a new tempo via the text input box or use the + or buttons to increase or decrease the tempo. There are also 1/2 and x2 buttons to double or half the tempo.

You can also adjust the tempo on the front panel of ML:2. The Up (+) and Down (-) buttons will increase or decrease the tempo. The Tap button will set the tempo according to the speed at which you tap the button.

Loop Size (beats)

This feature sets how often a Loop Reset output triggers. It also controls quantization of the Play/Stop control of ML:2. The value of Loop Size is in beats (quarter notes). Setting Loop Size to a value of “4” will cause a Loop Reset Trigger to happen every bar in a 4/4 time signature.

You may either enter a new Loop Size via the text input box or use the + or buttons to increase or decrease the Loop Size, one beat at a time. There are also 1/2 and x2 buttons to double or half the Loop Size.

Delay Compensation (ms)

Devices on an Ableton Link peer network can be timeshifted ahead or behind other Link peers. Sometimes the device you are synchronizing might have its own built-in latency that causes it to play a little bit behind the Link grid. In either case, you can use this setting to shift your clock output in time to better align with the Link music grid. Enter a value in the text input box or use the + or buttons to increase or decrease the Delay Compensation. This value is in Milliseconds.

This is an Ableton Link 3.0 feature. Your other Link apps or devices may not support Link 3.0 and thus, may not work with this feature.

Application Example

Start/Stop Sync is handy in the studio when recording your modular synth into Ableton Live or any other DAW that supports Link. Enable Start/Stop Sync in ML:2 and Ableton Live. Now, whenever you hit record in Live the ML:2 will start your modular synth sequencer in time with Live. Stopping the transport in Live will also stop ML:2’s clock playback.

Output Settings

Your ML:2 has two outputs: A and B. These outputs can be configured in a number of ways. By default, the A output will play a 4 PPQN clock trigger whenever ML:2 is playing. When ML:2 is stopped, Output A will output nothing. Output B will output a single trigger at the start of each loop when the clock is playing. If ML:2 is stopped, then Output B will do nothing.

Output Modes

The chosen output will generate a clock signal whenever ML:2 is playing. When it is stopped, the output will not create a signal.

Clock (Always On)

The output will always output a clock signal, no matter the playback status. This mode is useful for any devices that require a DIN Sync style clock. It is usually paired with a second output in Gate mode.

Common Clock Settings

Whether you have chosen “Clock” or “Clock (Always On)” there are several options to set up the clock to your sequencer’s requirements.


PPQN, or Pulses Per Quarter Note, indicates how many clock pulses to create per quarter note of time. Refer to the manual for the device you are syncing with ML:2 to find out what PPQN value that device is expecting.


Clock signal will consist of equal length triggers which can be 2, 5, or 10 milliseconds long.


Clock signal will be a square wave signal with a 10, 25, 50, or 75% pulse width.

Loop Reset Trigger

The output will generate a trigger at the start of each loop while the clock is Playing. Reset Triggers do not output when the clock is Stopped. This is useful for resetting your sequencer at the start of each loop. If your sequencer happens to fall out of sync for some reason, it will reset the sequencer at the start of the next loop. The trigger length can be 2, 5, or 10 milliseconds long. The timing of the trigger can be aligned with the start of the first clock pulse of the loop or it can arrive just before the start of the first clock pulse. Some sequencers do not like the reset trigger to arrive at the exact same time as the clock pulse.


The output will turn on (i.e. go high) when ML:2 is playing. When ML:2 is stopped, the output will turn off (i.e. go low). This acts as a switch to turn on or gate another device whenever ML:2 is playing. It can be paired with another output set to Clock (Always Running) to create DIN Sync-style clocking.

LED Dimming

In case you work in a dimly-lit environment, the WiFi status and button LEDs can be dimmed. Click the LED Dimming icon in the upper right header of the Control Panel. You will be presented with three levels of dimming.

Add WiFi Network

Click the Add WiFi Network button on the Home page or the Add Network link from the sidebar menu.

You will be presented with a list of available WiFi access points that The Missing Link could connect to. Click on one of the names in the list. Enter the password for that WiFi network and press the Submit button. Your ML:2 will store the WiFi network information and automatically reboot. Once it boots back up it will try to connect to that WiFi network with the password you entered. If the password is correct, your ML:2 will connect to the network successfully and the WiFi light will glow a solid color. If you entered an incorrect password, ML:2 will go back in to Access Point Mode after it determines that there’s no valid networks to connect to.

Saved Networks

Click the Saved Networks button on the Home page or the Edit Stored button in the side bar menu. You will be presented with a list of the stored WiFi networks that you’ve entered via the Add WiFi Network button.

Click the remove button to the right of the network name to that network. A dialog will appear to confirm you wish to delete that network from your stored networks list. Click Yes to confirm.

A message will appear notifying you that the network was removed. Click the REFRESH button to update the ML:2 system with this change.

Click IGNORE if you wish to do some other editing of stored networks or other settings in the Control Panel.

Access Point Settings

Your ML:2 has the ability to both connect to other existing WiFi networks or create its own network. When the ML:2 is making its own WiFi network it is in Access Point Mode. Any other Link devices can join this network to synchronize with the ML:2. The Access Point Settings page allows you to adjust the Access Point to your liking.

Name (SSID)

This is the name of the WiFi network the ML:2 will create when in Access Point Mode. The name is also used in the web address of your Control Panel. If you change the Name to “MyLink” then the web address to access the Control Panel would be http://mylink.local/

Hidden SSID

Enabling this will stop your ML:2’s WiFi network name from being listed in the WiFi menu of computers or mobile devices. This allows your WiFi network to be a little less discoverable in a situation such as live performance. You do not want people trying to connect to your ML:2’s WiFi network whilst you are performing!


This is the password needed to gain access to your ML:2’s WiFi network.

Require Password

Disable this if you wish to have an open network that anyone can easily join. This is nice for Link jams where you want to make it easy for others to join in the fun.

Always Start In Access Point Mode

Enabling this option will force ML:2 to always create a WiFi network on boot up, even if it can connect to another available local WiFi network. Sometimes you wish to keep your Link session separate from your home or studio WiFi network.

Updating Firmware

Upon entering the Update Firmware page, ML:2 will automatically ping the Circuit Happy server to check for an available update. If one is available, a button will appear that reads INSTALL UPDATE. Click it to start the update download and install process.

A window will pop up showing the installation progress.

After the install successfully finishes, ML:2 will automatically refresh the system and the Control Panel will reload when ML:2 is back online. You can verify that the new firmware version installed successfully by checking the firmware version listed at the bottom of every page of the Control Panel:

Beta Codes

At the bottom of the Firmware Update page, there is a “Beta Code” area. If you are a beta tester you would enter a secret beta code here to install a beta firmware. Unless you are participating in a beta testing program, please leave the Beta Code box empty.


I can’t connect to the Control Panel

Make sure that your computer is connected to the exact same WiFi network as your ML:2. If your computer is connected to the WiFi network with “My Network 5G” at the end but The Missing Link is connected to “My Network” (without “5G” at the end), they may not be able to see each other correctly.

2.4 GHz vs 5 GHz WiFi

ML:2 can only communicate on a 2.4 GHz WiFi antenna. If your WiFi router has combined both the 5 GHz and 2.4 GHz networks under one name (this is quite common) it is possible your computer or other devices are connected to the 5 GHz network and your ML:2 will be connected to the 2.4 GHz network. These two combined networks may not be able to send Link between them. It is best to name your 2.4 GHz network differently from your 5 GHz network. This way you can be assured that all the devices you wish to Link together are on the 2.4 GHz network.

Be sure there’s a trailing slash in the URL:

If that doesn’t work try dropping the .local from the URL:

When in Access Point Mode you can use this IP address to access your Missing Link:

When your Missing Link is connected to your own WiFi network, then the IP address is usually dynamically assigned by your WiFi router. You should be able to find the IP address of your Missing Link via the administration panel of your WiFi router.

Factory Reset

In the off-hand case that your ML:2 gets confused or lost from your network with nary a breadcrumb to find your way back to it, you can apply a factory reset to revert your ML:2 back to the state it was in when you first took it out of its pink and orange box for the first time.

How to Perform a Factory Reset

  1. Power off your Eurorack system’s power.
  2. Press and hold the Play and Tap buttons.
  3. While continuing to hold those two buttons down, power on your system.
  4. Keep holding the Play and Tap buttons until ML:2’s buttons blink and the “+” button blinks continuously. Note: if you decide at this moment that you do not wish to continue with the factory reset, stop and do nothing. Wait a few seconds and the reset will time out and boot up normally. If you do wish to reset ML:2, continue on to step 5 before that timeout period ends.
  5. Press the + button three times to initiate the factory reset.
  6. ML:2’s buttons will blink randomly and then it will reset.
  7. ML:2 should now be in Access Point Mode. The name of the Access Point will be the same as the serial number sticker on ML:2’s circuit board or the quick start card included in your box.

If you run in to any issues, don’t hesitate to Contact Us!