I think it’s helpful to show you the container’s theory with the aid of some simple diagrams. Basics: Containers – Practice will show you later, how it looks and what to do in SynthEdit itself.
If you have an effect like a delay for example, made out of a group of modules(grey modules), a container makes sense, because you could work on it in a separate window, without having other confusing modules and connections arround.
Inside the container you need an in and an out, to connect the container stuff with the source window modules. This special connection module, used to connect the container with the source window modules, is called IO Mod. In and out for sure means, you need 2 of them.
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