There is always 1 variation of 1 rackspace active (and the global rackspace is always active). So the only interconnections that can exist are between the current rackspace and the global rackspace.
- For audio there are specialized input/output blocks.
- For midi, you would have to resort to OSC or something like that (enough topics about that on the forum).
- Connections between widgets and plugin parameters can also cross the boundary between current rackspace and the global rackspace (using the same input/output blocks)
Some clarification on the rackspace/variation terminology:
- A normal rackspace has always at least 1 variation
- A rackspace is a collection of plugins, the connections between the plugins, the connections to input/output blocks, the connections to midi-in/midi-out blocks and widgets
- These widgets serve as ‘memory’, or better, persistence of the parameter-of-a-plugin the widget is connected to
- Variations keep track of different settings of these widgets. Let’s say you’ve connected a switch-widget to the on/off parameter of a chorus plugin. Then you could have a variation with this widget turned on and another one with this widget turned off.
- Rackspaces and variations can be controlled (if desired) using program change messages
- A variation of a rackspace can be tied to a song part
- The global rackspace has no variations
When would you typically use variations: When you use (almost) the same plugins with the same connections and the settings of the plugins do not have to change, except for the parameters that are connected to widgets.
When would you typically use another rackspace: When you have to use a (very) different set of plugins or the routing between the plugins (or the midi-in/out ) is rather different.
My way of (humble) usage (I play electric guitar):
- I use 7 different rackspaces with just 1 variation for several guitar sounds ranging from clean to rather deep distorted.
- I use an additional rackspace with 3 variations for my bass-guitar. These variations differ in the eq settings and the used ‘cabinets’. The one I use depends on the element I use on the bass-guitar.
I use a second instance of GP for drumloops:
- 1 rackspace with 1 variation combined with songs in a songlist. The loops for the drums are loaded from disk using gpscript and gp-presets. The name of the song is the name of the preset to load. The different songparts trigger different drumloops for intro, chorus, verse, bridge, etcetera.
- For 1 particular song I need a midi-bass plugin to play a bass-line. This song is tied to a second rackspace (with this bass plugin and the midi-file player)
For now, however, I would stay away from multiple GP instances. Just focus on getting a grasp of the basics. The same could go when it comes to using gpscript.
Maybe this clarifies the relationships somewhat.