Möbius 3

An Overlay is a collection of parameters that can be combined with the parameters defined in the session. Overlays replace the older concept of the Preset.

It is important to understand that using overlays is not required. Many will find it simpler just to set all parameters in the session. Until you reach a point where you feel you need what they do, I recommend you do not use overlays. They complicate how parameter behave and can make it difficult to understand why a change you made doesn’t seem to have any effect.

If you are upgrading from Mobius 2.5 or an earlier version of 3.x then you are automatically given a set of overlays that correspond to your old Presets. You can continue to use those in much the same way as you used presets, but I encourage you to think about whether you can stop using them and instead just use some of the new features built into the session.

Parameter Layers

The concept of parameter layers was introduced in the Using Sessions document. To understand how parameter overlays work, it is helpful to think of parameters as being organized into several layers. Each layer may have any number of parameter values in it. When a function or script needs the value of a parameter it searches through each layer from top to bottom until it finds a value. If a value does not exist in one layer, it moves to the layer below it, and continues until it finds a value.

The complete set of layers including overlays is shown in this diagram.

There is always one layer at the bottom called the session defaults layer. These are the parameters you set in the Edit Session window under the Default Parameters tab. For many uses of Mobius, this is the only layer you need. All of the parameters you want to use are set as session defaults and shared by all tracks. There are no other layers to think about.

Often though, you will want some tracks to use parameter values that are different than the session defaults. The syncMode parameter is one of those as are inputPort and outputPort. For example you may want the default syncMode to be Host to synchronize with the host transport, but want some of the tracks to use a syncMode of None so the recordings in those tracks can be freely created with any length. Or you may be using a mult-channel audio interface and want each track to have a differnet inputPort so that each track can record a different instrument plugged into a jack on the audio interface. Or you may want some tracks to use the quantize parmeter set to loop to execute functions when the loop reaches the end, and other tracks to not use quantization at all.

To make a track use a parameter value other than the session default, you create a track override layer in the Edit Session window. Any parameters you add to the track override layer will be used instead of the values found in the session defaults layer. In normal use, the track override layer will only contain a few parameters, with most parameters comming from the session default layer.

How Sessions layers and Overlays Combine

As mentioned, most uses of mobius will have two layers for each track. The session defaults and the track overrides. These are both defined in the Edit Session window and will persist as long as you are using that session.

The sessionOverlay when activated sits between the session default layer and the track override layer, and the trackOverlay sits above the track override layer.

If you have both overlays enabled, there are then four parameter layers that can each contribute parameter values.

Why would you want overlays?

Well, you don’t necessarily. You may find that you have them if you upgraded from an eariler Mobius release, because what used to be called Presets have been converted. THe session overlay is what used to be called the Setup Default Preset and the track overlay is what used to be called the Track Preset.

What made Presets different from Setups is that they could be channged quickly at any time. You could start using a track with a certain set of IO ports, synchronization settings, or quantization settings. Then in mid performace change presets and all of those parameters would change. Overlays are the same, they can be used to make rapid changes to many parameters at the same time.

This differs from editing the session. Sessions should be thought of as things you use for a long period of time, at least one “song” during a performance, and possibly an entire performance. Overlays can be changed any time, many times during a song if necessary. If you need to change more than one parameter at exactly the same time, overlays are a convenient way to do that. They are easier to use than a script that sets multiple paraeters, or binding several MIDI buttons to different parameters and pressing multiple buttons.

Why do overlays converted from Presets suck?

Presets were large. They contined around 45 parameters. For most people, presets were almost entirely the same except for a handful of commonly changed parameters like syncMode and inputPort. Once you had built a few Presets and wanted to start using something like switchQuantize set to loop at all times, then you would have to edit every Preset and make that change.

So after an upgrade, it is recommended that you revisit the overlays that were converted from Preset and remove all of the parameters that you don’t care about, parameters that can just use the session defaults.

Overlay best practices

Overlays should be as small as possible. They should only contain the parameters you need for a particular purpose. If you aren’t using one of the esoteric parameters like slipTime or muteMode, leave them out. Let parameters you rarely or never used just be defined by the session defaults.

When to use the Session Overlay vs. the Track Overlay

The session overlay supplies parameters for all tracks. Let’s say you have two instruments, a keyboard and a guitar. The keyboard is plugged into jack 1 on the audio interface and the guitar into jack 2. These are routed into Mobius as ports 1 and 2. The session default layer defines inputPort as 1 so you start recording the keyboard in all tracks. If you now want to switch to overdubbing with guitar, you could define a session overlay with inputPort set to 2 and activate that as the session overlay. All tracks will now receive on port 2.

Track overlays would be used when you want to make one or more tracks behave differently than the others. Let most tracks receive parameters from the sesison defaults or the session overlay, and for only those tracks that need to be different give them a track overlay.

Again, if you are wondering why or when you would use overlays, the chances are you don’t need to use them at all. Overlays will become visible only for older Mobius users that have used Presets in the past. If you are just starting out with a fresh installation there will be no overlays and you can consider whether you need them as time goes on.

Defining Overlays

Overlays are created and managed from the Parameter Overlays window which is displayed by selecting Edit Overlays from the Overlays menu. If this is a fresh installation, the overlays window will be mostly empty, if you have upgraded from a previous version, you should see entries in the overlay table on the left with names that correspond to your old Preset names.

To create a new overlay right click over the table on the left and select New.

A dialog pops up where you enter a name for the overlay. Like presets, all overlays must have unique names.

Once youu have defined some overlays, clicking on the name of one of them in the table will display a parameter tree in the center and a parameter form on the right.

Like the Edit Session window, clicking on a category name in the parameter tree will display a form containing parameters in that category, but only if they are included in the overlay. If you do not see a category form, it means the overlay does not contain any parameters from that category.

NOTE WELL: Parameter forms in overlays do not behave the same as parameter forms in the session editor. Overlay forms are “sparse” meaning they will only show the parameters included in the overlay. This is becaues they exist independently of any sessions, and to not know how they are going to be used so they won’t show darkened parameter labels for defaulted parameters. Initially all parameter forms in a new overlay will be empty.

To add parameters to an overlay, click and drag parameter names from the tree onto the form area. You then see fields being added to the form for each parameter you drag over. Once the form contains parameter fields you can change their values.

If you decide you no longer want to include a parameter in an overlay, click on the parameter label in the form and drag it onto the tree area. The parameter will be removed from the form.

As you click on overlay names in the table on the left, the forms will change to show only those parameters found in the selected overlay.

Overlay Table Menu

If you right click on an overlay name, a menu is displayed allowing you to copy, rename, or delete the overlay.

Activating Overlays

In order to use overlays, they must be activated. There are two ways to do this, either by selecting them in the session editor which makes them permanent, or by selecting them at runtime using the main menu or with bindings.

To specify a track overlay in the session, select a track from the track table and click on the Overlay category in the tree view.

The Track Overlay label will start out with dark text meaning this track does not override the session default. Click on it so that it turns bright, and select an overlay.

For older Mobius users, what is happening here is equivalent to what previous versions of Mobius did in the Track Setup window by selecting a Track Preset.

If you want all tracks to share the same overlay, a similar thing can be done in the Default Parameters tab of the session editor. The track overlay you select here will be used by all tracks unless they have a track-specific override. This is equivalent to what previous versions of Mobius did in the Track Setup window by selecting a Default Preset.

Temporary track overlays can be selected from the main menu.

When you select an overlay from the menu, it will only be sent to the track that currently has focus, the track with the white box around it in the UI. Note that unlike the old Preset menu, there is an item at the top named “[None]”. When you select this item, it removes any overlay that was previously selected for this track. Unlike Presets, it is permissible for a track to use NO overlays.

Finally a temporary track overlay can be activated using bindings. In the bindings window select the tab named Configurations. You will see the names of all defined overlays and sessions in the list box. Select an overlay and set the trigger you would like to associate with it as usual.

Once you have created a binding to an overlay, it can be activated with one MIDI or keyboard button press rather than interacting with the UI menus or session editor windows.

NOTE WELL: Overlays selected from the main menu or with bindings are temporary and will be removed when the track is reset using either the Track Reset or Global Reset functions. After the track is reset, the track will revert to using using the overlay defined in the session (if any).