Metaplugin is a flexible piece of software that loads other VST and AU plug-ins and lets you interconnect them arbitrarily. It is available in VST, AU and AAX format and can therefore also be used to bridge plugins in hosts that do not support either the VST or the AU format. Plug-ins can be dragged onto the freely resizeable interface, connections are made by dragging cables between the in- and outputs of the loaded effects. Chains can be saved so that the user can build custom effects out of existing modules.
As an extra, a flat-summing four band crossover filter and a mid-side matrix are included in the package. This way, multi-band and mid-side versions of existing plug-ins can be built instantly.
Metaplugin supports up to 6 in-out-channels. The user can load it, e.g., into a 5.1 channel of the host and chain plug-ins on all six channels (and across channels). Also, the dry/wet amount going through each of the loaded plug-ins can be adjusted (shift-clicking on the plug-in rectangles turns them into horizontal sliders).