for version 0.10.0


RaySession is an audio session manager for GNU / Linux. It allows you to start several audio programs in the same session, to save their projects together and thus to avoid multiple operations to return to a given configuration.

To be launched in RaySession, it is very much preferable that these audio programs be compatible with the NSM protocol, and many are already, among others Ardour, Qtractor, Carla, Guitarix, Mamba, Patroneo, ZynAddSubFx …​

RaySession assumes that your audio setup is working for audio production, if not, fix this first and don’t waste your time trying to use RaySession.

Now let’s see how to use it.

Simple use example

For audio production under GNU / linux, it is highly recommended to use the JACK server. Before creating or starting a session, make sure the JACK server is running, RaySession has no direct relation to JACK, however the programs you are going to launch in your session will need it.

Let’s take an example where to compose a song, we will need Ardour and Guitarix softwares, make sure that these 2 programs are installed.

To create a new session, click at the top left on New Session (or Ctrl+N). A dialog window appears.

New session

At the top right you can see the root session folder, this is where the sessions will be saved (a RaySession session being a folder containing a file raysession.xml).

Enter the name you want for this new session in the field provided. To put your new session in a sub-folder, type the name as follows: sub-folder/my session.

The session template multiple choice box lets you choose between

  • An empty session template

  • A template with memory of JACK connections

  • A scripted template with memory of the JACK configuration

  • A template with basic session scripts (for advanced users with shell scripting knowledge)

  • All the session templates that you have created yourself.

First, keep the template on With JACK patch memory , click Ok to start your session.

Session launched

The session part of the window becomes active, at the top is written the name of your session, and your session already contains a client program called JACK Connections. This client will save and redo the connections of the JACK patchbay.

To add Ardour to your session, click on the Application button (or Ctrl+A), the application dialog will appear (more details in the Add application window section). On the right side, find Ardour (Depending on your version of ardour, it may be called Ardour5 or Ardour6) and double-click on it.

Add Ardour to the session

An Ardour client appears below JACK Connections and Ardour starts up (normally directly with an empty Ardour session).

Do the same with Guitarix.

Session ready with Ardour and Guitarix

In Ardour, add a track (Menu: Track → Add a track), in the Ardour window that has appeared, name the track Guitar and put the multiple choice box configuration on Stereo.

Add a track in Ardour for Guitarix

Open the JACK Patchbay, for this go to ControlShow JACK Patchbay (or Ctrl+J). The patchbay appears at the right of the window.

Connect the Guitarix input to a hardware input and the Guitarix outputs to the inputs of this new Ardour track. Make sure your Guitar track inputs are not connected to the hardware inputs.

My session patchbay

Here you have a configuration where you can directly record the sound of your guitar processed by Guitarix in Ardour. If you don’t have a guitar, all you have to do is sing out of tune into a mic or tap a cushion, this is just an example.

Now go back to the RaySession window, and save the current session by clicking the floppy disk button to the top right (or Ctrl+S). It is highly recommended because it is very practical to assign a global keyboard shortcut of your system to the save of the current session. This will depend on your desktop environment, but just assign the Ctrl+Meta+S shortcut to the command ray_control save (Meta is the Windows key), so you won’t have to return to the RaySession window to save the session.

Now close the session by clicking on the red cross at the top right (or Ctrl+W).

Once the session is closed, click on Open Session (or Ctrl+O), double-click on the session you just created to re-open it.

You will find the programs and their projects as well as the JACK connections as they were when you closed the session, and everything therefore works without any further manipulation. One of the advantages of modularity in this specific case is that once you have finished the guitar records, you can stop Guitarix so as not to overload the processor unnecessarily, and it will still be easy to restart it if necessary.

Overview of session tools

Top row

Top line of the session frame

From left to right:

  • the menu button gives you access to

    • save the current session as a template
      The created session template will then appear in the multiple choice of session templates in the New Session dialog window. Be careful, however, all the files of the session will be saved in the template, so you should not do this if the session contains a lot of audio files. firstly, the copy will be long, secondly, you run the risk of unnecessarily multi-copying files which will take up a lot of space.

    • Duplicate the current session
      This is the equivalent of the well-known "Save As …​", except that RaySession has to stop and restart most programs to switch between sessions. Avoid duplicating a session with a lot of audio files, it could take a long time, but fortunately such an operation can be stopped.

    • Rename the session
      It will then be necessary to stop all the clients.
      Alternatively, you can rename a session by duplicating it and then deleting the folder from the initial session.
      You can also rename a session by renaming its folder, but BE CAREFUL, this session must not be loaded!

  • the pencil-shaped button gives you access to the session notes.
    Write here the information you need, the physical settings, the lyrics of a song, the recipe for granny’s cassoulet …​ however do not write a novel in 3 volumes, other tools are much more suitable, and notes are limited to 65,000 characters for technical reasons. The pencil is green when notes exist, it is orange when the notes window is open, otherwise it is transparent.

  • the name of the loaded session (here my session)

  • the Abort session button which allows you to close the session without saving it

  • the Close session button ,which saves and closes the current session.
    Note that you do not need to close the current session to start another. Some clients are able to switch from one session to another and it may take a lot less time than closing everything and restarting everything.

Bottom row

Bottom line of the session frame

From left to right:

  • the folder-shaped button to open the session folder with your file manager

  • the yellow star-shaped button that pulls down a menu containing your favorite applications if there are any

  • the Application button which allows you to add to the session a factory application template or that you have created yourself. This is the recommended method for adding a client. see Add application window.

  • the Executable button which allows a program to be added to the session from its executable. You will need it if you want to add a program for which there is no template. see Add executable window.

  • the reverse button to return to a previous state of the session. This requires having the program git installed, else this button will not appears.
    See Snapshots for more details.

  • the server status indicator.
    Server states can actually be very stealthy, but they are displayed for a long enough time that you can see them. The server status can be:

    • off: no session loaded

    • ready: the session is running

    • launch: launch of the session’s programs

    • copy: a copy is in progress, for a session duplication or to save the session as a template

    • close: the session is closing

    • snapshot: A snapshot of the session is being taken, so you can revert to the current session state.
      see Snapshots.

    • wait: The server waits for you to close yourself non-saveable programs

    • script: a script is activated

    An information or progress window is displayed if you click this status indicator if it is on copy , snapshot, or wait.

  • the Save Session button

  • the trash, here you will find the clients that you have deleted. You can then restore them in the session or permanently delete all the files they created in the session folder.

Overview of a client

trame d’un client

A client contains from left to right:

  • The client icon that you can click to bring up a menu with the following actions

    • Save as application template
      The created template will then appear in the Add application window. This then allows you to directly launch a client with the desired configuration (Ardour with such tracks, Hydrogen with such drumkit…). Be careful, this copies all the client’s files so avoid doing this if the client contains a lot of audio files.

    • Rename
      Change the client name located to the right of its icon, it is a purely visual name that can help you organize yourself.

    • return to a previous state
      Returns only the client to a previous session state, see Snapshots.
      However, you will not be able to go back to a state prior to a session renaming, so you must go back the entire session.

    • Properties
      Displays the client properties window

    This menu is also accessible by right-clicking anywhere on the client.

  • The name of the client (here Carla), which can be easily changed by right-clicking → Rename

  • depending on the type and capacity of the client you can see here

    • an eye (possibly crossed out), this means that the client is NSM compatible and is capable to show or hide its window by clicking on the eye.

    • a Hack button, it means that the client is not NSM compatible, or at least that it is not launched with this protocol. Clicking on Hack allows to change the way it is launched by opening the client properties window on the Ray-Hack tab.

  • The Start button which is grayed out if the client is already started.

  • the Stop button which is grayed out if the client is not started.
    If you stop the client and it is still not stopped after a while, the button turns red and you can click on it to kill the client. But stay relaxed, and only use it if it really seems completely inert, it could cause problems, even if nobody will send you to jail.

  • the state of the client which can be

    • stopped: the client is stopped

    • ready: the client is running and everything is ok

    • open: the program is opening its project, please wait a little bit.

    • close: the program is closing

    • launch: if it stays on the launched state, it means

      • if it is a Ray-Hack client, that it does not have a configuration file

      • if it is started as an NSM client, if it is not NSM compatible, and therefore any save is in vain. It may be practical to launch certain programs in this way, such as a patchbay (Catia) or a utility whose state you do not need to save (Qrest).

    • switch: the client changes projects during a session switch

  • the floppy disk button that allows you to save the client.
    If over this floppy you see

    • three red dots: the client contains unsaved changes

    • a green V: the client does not contain unsaved changes

    • an orange exclamation mark: It is not an NSM client, and it is impossible to save its project, you will have to do it yourself

  • the red cross which allows you to send the client to the trash

Add application window

The window for adding application is launched by clicking on the Application button (or Ctrl+A).

Add Application window

The list of available applications is on the right. If the software you want to add is not present here, see Add a program not provided.

Top left is the filter block

Filter block of Add Application window
  • the filter field allows you to enter a character string, only templates containing this character string in their name will appear.

  • the Factory checkbox displays the templates integrated into RaySession or provided by your distribution

  • user displays the templates created by the user by doing Save as application template

  • NSM displays the NSM compatible clients, or launched as such

  • Ray-Hack displays clients launched without NSM protocol

Bottom left the information block on the selected template on the right

Informations block of Add Application window
  • at the top right of this block, a star, click on it to add it to favorites or remove it from favorites

  • If it is a user template, a User button allows you to delete this template

  • the button at the bottom right of this block allows you to access all the properties of the template, as in the [client_properties], except that nothing is editable.

Tip: This window is designed for very fast app addition, and behaves like Alt+F2 on your desktop.
For example, from the main RaySession window, to add Carla type Ctrl+A , then carla, select the correct template with the Up/Down arrows, then Enter.

Add executable window

The window for adding an executable is launched by clicking on the Executable button (or Ctrl+E).

Add Executable window

You will need to go through this window if you want to add a client that does not appear in the list of the Add application window. This window is very simple, a field to enter the executable, an NSM Protocol box, an advanced options button.

Leave the NSM protocol checked if:

  • the program to launch is NSM compatible (if it is not in the list of applications, please let us know!)

  • the program to run is a utility for which there is no need to save any project (QRest, Catia…). The state of such a program will remain on launch and will never be ready, it is irrelevant since they do not have a project to save.

If you leave the NSM protocol checked, it will not be possible to use the absolute path of an executable to add it, the executable must be located in a location provided for this purpose (you will not be able to launch /usr/bin/my_program, but my_program). You cannot enter arguments here, with or without the NSM protocol.

Unchecking NSM Protocol is equivalent to launching the program with the Ray-Hack pseudo-protocol.

If you click on the advanced options button, an advanced options block appears with

Advanced Add Executable window
  • the Start the client checkbox , if you uncheck it the client will be added but not launched

  • the multiple choice box Prefix Mode, this defines the prefix of the name of the client’s files

    • on Session Name, the file names will start with the session name, this is the default value

    • on Client Name, the file names will begin with the name provided by the client itself, as is the case with New Session Manager

    • on Custom, the file names will start with the value you enter in the Prefix field just below.

  • the Prefix field which is only active if Prefix Mode is set to Custom.

  • the Client ID field (client identifier). Enter only alphanumeric characters or '_'.
    This is useful if you want to catch and launch existing projects in the session with an executable. This is useful if you want to load in the session projects created outside a session. There is no method to make it easier, it depends a lot on the program you are using. RaySession will insult you if you enter a client ID that already exists in the session.


The JACK patchbay is not displayed by default. You can display it by clicking on Control and then Show JACK Patchbay (or Ctrl+J). The patchbay contains all the JACK AUDIO and MIDI ports that you can interconnect.

Obviously, if JACK is not started, this patchbay will be empty.

It is advisable to have the A2J bridge running if you want to work properly with MIDI. You can configure this via Cadence, Studio Control, or via the command line utility a2j_control.

RaySession does not include tools to configure the JACK server, QJackCtl, Studio Control, Cadence, or the command line utility jack_control do this job very well. Note that this patchbay also works with PipeWire.


Patchbay overview

This is what your patchbay can look like. Here there are 7 boxes:

  • a system box with your ports corresponding to the hardware inputs (microphone, guitar…​)

  • a system box with your ports corresponding to the hardware outputs (headphones, speakers…​)

  • an a2j box with your ports corresponding to the MIDI hardware inputs

  • an a2j box with your ports corresponding to the MIDI hardware outputs

  • a PulseAudio JACK Source box

  • a PulseAudio JACK Sink box, sound from firefox and all non JACK applications comes from theses ports

  • a Guitarix box

Here A2J and pulse2jack bridges are launched.

You notice that 4 of these boxes are surrounded by a decoration (2 system and 2 a2j), these are the boxes that contain the hardware ports (your audio interface, your USB piano, any controller…​).

Some audio ports are grouped into subgroups, which we will call portgroups. These portgroups are mostly stereo pairs automatically detected by the port names. This is the case here for :

  • system:capture 1/2

  • system:playback 1/2

  • PulseAudio JACK Source:front L/R

  • PulseAudio JACK Sink:front L/R

  • Guitarix:out 0/1

These portgroups facilitate the connections and allow a better general readability.

The blue curved lines correspond to the audio connections. You can observe that :

  • hardware input audio ports are connected to PulseAudio JACK Source.

  • the PulseAudio JACK Sink ports are connected to the hardware outputs

  • only the first port of system is connected to the input (in 0) of the Guitarix software

  • the audio ports of Guitarix are connected to the hardware outputs

Make and break a connection

You can establish a connection between 2 ports as long as they meet the following conditions:

  • he ports are of the same type (you can’t connect an audio port to a MIDI port)

  • one is an input port, the other is an output port

Intuitive Method

To connect or disconnect two ports, click on a port without releasing the mouse button, drag the cursor to the desired port and release the mouse button.

Alternative method

Right click on a port, it will display a drop down menu, choose Connect then the desired port. Click elsewhere to make this menu disappear. The advantage of this method is that it allows you to quickly connect a port to several others, the menu remaining displayed during the connections.


Right click anywhere on the patchbay to display the menu. This menu is also present in the RaySession menu (Patchbay menu). It will allow you to :

  • switch the patchbay to full screen

  • Filter ports: show only AUDIO or MIDI ports or both

  • adjust the zoom level

  • refresh the canvas: ask JACK again for the list of existing ports and their connections

  • Canvas Preferences: display a window of options
    All changes in this window take effect immediately. Hover over the boxes to see the tooltips.

Shortcuts you should know

  • A double click anywhere switches the patchbay to full screen.

  • Ctrl+Mouse Wheel allows you to zoom in/out.

  • Alt+Mouse wheel allows to move the view horizontally.

  • The wheel button is used to move the view

  • Ctrl+middle mouse button cuts all connections passing under the cursor

Burst Connections

It is possible to connect a port or a portgroup to different ports quite quickly. You just have to end your connections with a right click. A video will be much more explicit.

Here we want to connect the multiple outputs of Hydrogen to the Jack-Mixer tracks. In the video the blue circles appear with a right click.

Passing connections from one port to another

Sometimes it is less tedious to switch connections from one port to another than to undo and redo everything. To do this, start from the port that contains the connections and act as if you wanted to make a connection, but go to the port to which you want to switch the connections.

  • This only works if the destination port does not contain any connections

  • It works from port to port or from portgroup to portgroup but not from port to portgroup

In this video we have a rather complex case where the source is plugged into 3 Band Splitter. The bass and treble (Output 1 and Output 5) are sent directly to EQ6Q Mono while the midrange (Output 3) goes through the distortion GxTubeScreamer first. We want to insert the Dragonfly Room Reverb before the EQ6Q Mono equalization.

Note that with the right-click connection and the switching of connections from one port to another, it is very quick to integrate a new plugin in a chain, as here where we plug Plujain Ramp Live between Dragonfly Room Reverb and EQ6Q Mono.

A2J ports

ports a2j

The MIDI ports provided by the A2J (Alsa To Jack) bridge have a hole at the end to identify them. Their real name is a long name, but that’s about the only thing that differs from the other MIDI ports.

Control Voltage ports (CV ports)

ports CV

Control voltage ports, commonly called CV ports, work like regular audio ports, however, they can control one or more parameters with much more precision than MIDI ports. As their stream is not meant to be listened to, it is not possible to simply connect a CV output port to a regular audio input, as this could damage your headphones, your speakers, and maybe even your ears.
If you still want to do it, right click on one of the ports, then Connect, then the DANGEROUS menu.
You can’t say you weren’t warned, and it’s almost impossible to do this by mistake.

On the other hand, connecting a classic audio output port to a CV input port is perfectly possible, no problem.

Client Properties Window

A client’s properties window opens from the client menu by clicking Properties.

The client properties window has 2 tabs, a General tab and a tab specific to the protocol used by the client. Depending on the client protocol, the second tab is called NSM, Ray-Hack or Ray-Net.

General tab

Client properties

The first block of the General tab displays the client ID, protocol, label, description and icon.
If you do not edit them, the label, description and icon are taken from the .desktop file associated with the launched executable, if found.
If you want to know the .desktop file used, type ray_control client CLIENT_ID get_properties in a terminal (replacing CLIENT_ID with the client identifier).

Then comes the block of snapshots, see Snapshots.

The checkbox Prevent stop without recent or possible save concerns the window that may appear when you ask a client to stop. If this box is unchecked, then the client will be stopped without a window warning you.
If the box is checked, the window will warn you when

  • the client is unsaveable from RaySession

  • we know that the client contains unsaved changes

  • the client appears not to have been saved for more than a minute

Whether or not to check this box depends only on the importance of your client’s save, it’s up to you to judge. That said, if the warning is annoying, just check Don’t prevent to stop this client again in the warning window and Prevent stop without recent or possible save will be unchecked.

NSM tab

NSM Client properties

The Name of the client here is provided by the client himself.
The capabilities are those which are transmitted by the client at its start-up. If the client has not yet been started, this field is therefore empty.

Editing the executable allows you to change the command that launches the client. Only change it to another executable capable of loading the existing client’s project. This is useful for example if you have two versions of Ardour, one running with the command ardour, the other with Ardour6, and you want to change which version to use.

Editing the arguments is strongly discouraged, and is especially not suitable for loading a file as an argument.

Ray-Hack tab

If the client is a Ray-Hack type, here many fields are available to you. This is not necessarily good news, the idea is to be able to load a program into the session that is not (yet) compatible with NSM. If properly implemented in the client, the NSM protocol will always be much more comfortable to use and more reliable than this hack. That said, if we can expect the NSM implementation in all audio programs, this is not the case for other programs which can still be useful in the session.

The Ray-Hack pseudo-protocol uses the attributes of proxies (nsm-proxy or ray-proxy), except that the client is launched directly in the session.

Ray-Hack Client properties

Launch block

ray hack launch
  • the Folder is the folder name of this client in the session folder. The program is launched from this folder.

  • the Executable is the command that starts the program

  • The Config file will be the project file that we want to open with this program. It is more than highly recommended to reference a file in the client folder.
    The variable $RAY_SESSION_NAME will be automatically replaced by the name of the session.
    If this field is empty, the client status will always remain launch and will never be ready. In some cases, therefore, it may be useful to type anything here rather than nothing.

  • The Browse button opens a dialog box to find the project file and fill in the Configuration file field

  • The Arguments field includes the arguments passed to the Executable command
    the arguments are split as they would be in a terminal, don’t forget the " or ' if necessary.
    For example to reproduce my_command my_argument_1 "my argument 2" enter my_command in the Executable field and my_command my_argument_1 "my argument 2 " in the Arguments field.

Signals block

ray hack signals
  • Save Signal can be only rarely used. It can be SIGUSR1 for programs compatible with the old LASH protocol. Otherwise leave it on None, if there is no save method, we cannot invent it.

  • Stop Signal will usually be SIGTERM. Only change it if this signal does not close the program correctly.

  • If Wait for a window before considered it ready box is checked, then the client status will only change to ready when a window appears.
    If wmctrl is not installed, or the window manager does not seem to be compatible with it, then the client status will be ready half a second after it is launched.

With ray_control you can assign signals other than those offered in the multiple choice boxes. For example ray_control client CLIENT_ID set_properties save_sig:22 will define the SIGTTOU signal for the client CLIENT_ID save.
Type kill -l to see the available signals and their numbers.

Non-saveable management block

ray hack non saveable

This block is active only if the Save Signal is set to None.

  • if Tell user to close program himself at session close is checked, the client will be considered as not saveable and an orange exclamation mark will appear in front of its save icon. When closing the session, RaySession will wait for you to close the program yourself because it is impossible to know if it contains unsaved changes.

  • If Try to close window gracefully is checked, then at session close, RaySession will try to close the window as if you were closing the program window. This is very useful when the program reacts by closing if there are no unsaved changes and displaying a close confirmation window in the opposite case (most programs react in this way). If wmctrl is not installed or the window manager does not seem to be compatible, you will have to close the program yourself in any case.

Test area

ray hack test zone

The test area allows you to test the start, stop, and save settings set in this window without having to Save the changes.

Network Sessions

A network session allows you to launch another session on another machine at the same time as your session. This can be particularly useful if you are using net-jack to unload your machine from part of the DSP, if you have greedy effects running on another machine for example.

Network sessions operate on a master-to-slave basis. A session is master and can have several slave sessions which are themselves masters of other slaves, but such a scenario seems completely out of the ordinary. Organize yourself simply: one master, one or more slave(s).

To launch a network session (therefore a slave), launch the Network Session application template from the applications window and follow the instructions.

Add a network session

You will have to start a daemon on the remote machine with the command ray-daemon -p 1234 (1234 is an example, put the port you want). This daemon displays something like this in the terminal:

[ray-daemon]URL : osc.udp://`
[ray-daemon]      osc.udp://nom-de-machine:1234/`
[ray-daemon]ROOT: /home/utilisateur/Ray Sessions reseau
Configure a network session

You will need to copy one of the two URLs into the network session invitation window. The first (which begins with osc.udp://192.168.) must work for sure, the second will work only if the name of the slave machine is correctly entered in the file /etc/hosts of the master machine. However, entering the name of the slave machine in /etc/hosts and using the second URL is preferable, because the address in 192.168. will move if you connect your slave machine differently (wired, wifi), or if you reinstall the distribution.

You now have 2 RaySession windows on your master machine, one controls the master session, the other the slave. You will recognize the slave by the fact that it does not have a toolbar (New Session, Open Session, Control), nor Abort session and Close session buttons.

network session child

The slave window is hideable as is the case in many NSM programs.

network session client

If you run raysession -p 1234 on your slave machine, you will have the slave session window in duplicate, one on each machine.

Tip: Put this ray-daemon -p 1234 in your slave machine startup.

Add a program not provided

If the program you want to add does not manage a project to save, click on Executable, enter the name of the executable and click on Ok. Otherwise follow this example.

We want to add Audacity to the session here. Audacity is chosen as an example because it is known and generally installed on audio distributions. This is not necessarily a very suitable program for the modularity of an audio session given the way it handles JACK.

Click Executable (or Ctrl+E). In the Add executable window, Uncheck the NSM Protocol box, type audacity in the Executable field and click Ok.

Add Executable window well done

A new client is created, its properties window opens on the Ray-Hack tab and Audacity is launched.

In Audacity, we will directly save an empty project in the client’s folder. The client’s folder is located in the session folder and has the name given after Folder: at the top of the Ray-Hack tab. We will call the project EXACTLY like the current RaySession session. To do this, in Audacity, go to Menu → File → Save project → Save project.

Save empty Audacity project

Click Validate at the possible warning window.
In the save files box that opens, you will find the session folder at the bottom left (see Provide bookmarks for session folder), click on it to enter it. Inside this you should see the client’s folder as it appears at the top of the Ray-Hack tab, enter this folder. At the top left of the backup box, type the exact name of your session in the Name: field then validate.

Where to save Audacity project

Close Audacity.
At the top right of the Ray-Hack tab of the client properties window, click Browse.

Load CONFIG_FILE window

select the Audacity project you just created, its name starts with the session name and ends with .aup.

If all went well, the Configuration File field became $RAY_SESSION_NAME.aup and the Arguments field became "$CONFIG_FILE".
Check the boxes Wait for a window before being considered ready, Ask the user to close the program himself and Try to close the window gracefully. Click in the bottom right corner on Save Changes.

Ray-Hack tab of Audacity client well done

Launch the Audacity client and verify that the Audacity window has the name of the session.
Click on the Audacity client icon, in the drop-down menu choose Save as an application template, and enter Audacity the field of the dialog box that has appeared. Now when you want to launch Audacity in the session, all you have to do is launch the Audacity template from the Add application window.

Note that the client’s save button is behind an orange exclamation point, this means that RaySession is not able to save its project and that you will have to do it yourself.

Depending on what program you want to add to the session, it might not always be that easy. Some programs will require an argument that precedes the configuration file, in this case type my_program --help or man my_program to know how to load a project when the program starts, and adapt this in the Arguments field.

Import an NSM session

To import a session created with Non Session Manager or New Session Manager, move or copy the session folder to the RaySession root sessions folder (default ~/Ray Sessions). Then click Open session, your session should appear in the list of sessions, double-click on it.

RaySession will not rewrite clients added or deleted to the session.nsm file, as long as you open an NSM session with RaySession you must continue with RaySession.

The daemon’s options

Daemon options are services which can be activated and deactivated via the Control button at the top right of the main window, or via the options menu in the menu bar.

Daemon options

Here are the details of the different options:

Provide bookmarks for session folder

In audio production, creating audio or midi file with one program and load it into another is an usual case. This option offers something purely practical: a shortcut to the current session folder in your file manager and in the dialog boxes provided for fetching or saving files. It simply avoids wasting time browsing through your personal folder tree to find a file that you have put in your session folder, since that is where it belongs.
Of course, this shortcut is deleted when the session is unloaded.
Technically, shortcuts are created for GTK2, GTK3, QT4, QT5, KDE and FLTK.

Auto Snapshot at Save

This option is far from being trivial, it allows you to take a snapshot of the session after each session save. This means that in case of a technical or artistic error you will be able to find the session in the state it was in at the moment of the snapshot. This option requires that you have the git program installed. See Snapshots for more details.

Desktops Memory

If this option is activated, RaySession will save (or attempt to save) the number of the virtual desktop on which the client windows were located when the session was saved. So when you restart the session or the clients, the windows will be redispatched to the desktops on which they appeared. This option requires you to have the program wmctrl installed to work, and probably will not work with Wayland.

Session scripts

Disable this option to not activate any session script, and thus open, save or close a session completely ignoring the scripts associated with these actions. These scripts are used by sessions with JACK configuration memory. See Session scripts for more details.

Remember optional GUI states

This option only concerns NSM clients capable of showing/hiding their graphical interface. Without this option, some of them will always start hidden, others will remember if they were visible when they were last saved. With this option enabled, the graphical interfaces will be displayed when the session is ready if they were visible during the last save or if the client has never been launched.


Snapshots require you to have the program git installed, if you don’t have git, the reverse button does not appear and it is not possible to take or return to a snapshot.

A snapshot stores files and their contents at a specific time. Large files and files with certain extensions such as audio and video files are ignored, otherwise the snapshot process will take too long and the size of the session folders will needlessly double. This is actually not very annoying, on the contrary, since your recent audio files remain present when you go back to a previous snapshot.
If despite everything the snapshot process turns out to be long, a window appears and you can safely cancel the current snapshot. If you cancel it, the automatic snapshot will no longer take place for this session.

The interest of the snapshots lies in the fact of being able to return to the previous moment of the session, before having had this brilliant artistic idea which turned out to be null and void, before having attempted a recutting of the samples with the microcoscope which finally killed all forms of musicality, before a program crashes for some reason unknown to the police…​

Don’t worry, going back to a snapshot won’t stop you from getting back to where you were.

To revert the session to a snapshot, click the reverse button located to the right of the Executable button.


Select the snapshot you want to revert to and click Ok. A new snapshot is taken, the session closes, the desired snapshot is recalled and the session reopens.

It is also possible to return only a client to a previous state of the session by right-clicking on the client,then Return to a previous state. If you want you can edit for each client the files ignored by the snapshots in the [client_properties].

With the Automatic snapshot after save option, a snapshot is taken immediately after each backup of the session, unless there is no change since the previous snapshot. To take a snapshot at another time, click on the reverse icon to the right of the Executable button and on Take a snapshot now, this has the advantage of being able to name the snapshot and thus having a more meaningful time mark than the date and time of the snapshot.

Session scripts

Session scripts allow you to program personalized actions when opening, saving and closing the session. They are used in particular for sessions with JACK configuration memory.
Knowledge of shell scripting is required to edit these scripts, but anyone can use them.

Session scripts are located in a folder ray-scripts located either in a session folder or in a parent folder.
For example, for a session being in:
~/Ray Sessions/with_foo_script/my session

the session scripts folder may be

~/Ray Sessions/with_foo_script/my session/ray-scripts
~/Ray Sessions/with_foo_script/ray-scripts
~/Ray Sessions/ray-scripts

The advantage of such behavior is to be able to script a set of sessions without having to copy the scripts there, but above all to deliver an unscripted session when it is transferred to someone else for collective work.
Only the script folder closest to the session in the tree will be considered. Thus, a ray-scripts empty folder in a session will disable scripts for that session.

To edit the scripts, start by creating a session with the template with the basic scripts, this is a template session with scripts that does not include any particular action. Go to the folder ray-scripts in the session folder, you will find the files load.sh, save.sh and close.sh. In each of these scripts, ray_control run_step corresponds to the normal action performed (depending on the script: load, save or close the session). If one of these three scripts is of no use to you, delete it, it will save time not to go through that script.

The script files must imperatively be executable to work.

You will probably need the command line utility ray_control to perform actions relating to a particular client. type ray_control --help to know all its possibilities, see also Control RaySession from the command line.

JACK memory configuration session template uses session scripts, but we can also imagine many possible actions according to your needs and desires, for example:

  • define a specific order for launching clients when the session is opened (an example is provided in the source code)

  • make a backup copy of the session on an external hard drive each time you close it

  • send a Ctrl+S shortcut to non-saveable client windows when saving the session (an example is provided in the source code)

  • Turn on the red light at the entrance to the studio when opening, turn it off when closing

  • Start the coffee machine at the end of the session (stupid example, go and press the button on the coffee maker, anyway you will have to change the filter!)

  • Make many, many, many mistakes that will crash your session, be careful of course!

JACK configuration memory

It is possible thanks to session scripts to automatically recall the JACK configuration specific to a session before loading it. This behavior may remind some of the operation of LADISH studios, much better done, at least that’s what is hoped.

In which cases to use it

This can be useful:

  • If you need to use a specific audio interface for the session

  • If you are working on multiple projects with different sample rates (such session at 44100 Hz, such session at 48000 Hz).
    This will prevent you from having to reconfigure, stop and restart JACK yourself, or even avoid forgetting to do so and being insulted by certain programs.

  • If you want to avoid loading a very DSP-intensive session (for example in the mixing phase) with a too small buffer (128 for example).
    Note that on most audio interfaces it is possible to change the buffer size hotly (without restarting JACK).


The Session scripts option must be enabled (This option is enabled by default).

To use the JACK configuration memory, create a new session from the With JACK configuration memory template. It is in fact a scripted session (see Session scripts) which launches a script supplied with RaySession, but which is completely external to it, so RaySession still has no direct relation to JACK.

Read the information window on this subject then validate. JACK restarts then your session starts.

Working principle

Each time the session is saved, the JACK configuration is saved in the session, in the jack_parameters file.
Before opening the session, JACK is restarted if the configuration of the session is different from the current configuration of JACK.
After closing the session, JACK is restarted if necessary with the current configuration before opening.

The configuration of the PulseAudio → JACK bridges is also saved and restored with the JACK configuration.

If you open this session after having copied it to another computer, the JACK configuration will not be recalled but will be overwritten when saving. Only the sampling frequency of the session will be used.

Special cases

To open a session without reloading its configuration from JACK:

  • disable the Session scripts option

  • open the session

To change the JACK configuration of a session:

  • Start JACK with the desired configuration

  • Disable the Session scripts option

  • Open the session

  • Re-enable the Session scripts option

  • Save the session

To make an old session sensitive to the configuration of JACK

  • copy the folder ray-scripts of a session with memory from the JACK configuration to the session folder

  • Activate the Session scripts option

  • Open the session


  • move the session to a sub-folder containing the good one ray-scripts folder

  • Open the session

Under the hood

RaySession is really just a GUI for ray-daemon. When you launch RaySession, the GUI launches and connects to the daemon, and it stops the daemon when closed. The graphical interface and the daemon communicate with each other by OSC (Open Sound Control) messages, as is the case between the daemon and the NSM clients. Thus, you can connect several graphical interfaces to a daemon, even remotely. Type raysession --help to see how.

It is not forbidden to have several daemon instances launched simultaneously, so if you launch RaySession while an instance is already launched, it will launch a new daemon. However, this way of working being unusual, the use of a single daemon is favored. So, if a daemon is running and it has no GUI attached, raysession will connect to that daemon by default.

Control RaySession from the command line

the command ray_control lets you do just about anything you can do with the GUI, and a little more. type ray_control --help-all to know all the possibilities.

In case there are multiple daemons started (see Under the hood), ray_control will only consider the one that was started first, unless you specify its OSC port with the --port option or RAY_CONTROL_PORT environment variable.

One might think that there is no point in using ray_control since the command oscsend allows to send an OSC message to the daemon, but it is false.
Firstly, because oscsend allows you to send messages but not to obtain information in a simple way (which are the active clients? What is the executable of such and such client? …​), secondly, because the command ray_control will end when the requested action is taken, for example ray_control open_session "my session" will end when the session is loaded.

Remember to assign ray_control save to a global shortcut of your desktop environment (Ctrl+Meta+S), this will save you a lot of time!

Frequently Asked Questions

  • Is it still worth running Ardour (or another NSM compatible DAW) directly rather than in RaySession?

    Except for a really tiny project, no. If you are using Ardour, always run it from RaySession, firstly, the automatic snapshot after save can be of unexpected help to you, secondly, you are not immune to needing another program even if you did not plan it.

  • Can I launch an Ardour session launched normally into a RaySession session ?

    You will find in source code here a script named ardour6_from_external_to_session.sh. Before to use it, backup your ardour session directory. Download this file, set it executable and execute it with a .ardour file as argument, it will adds the ardour project to the current session, or create a session if no session is loaded.