generic MasterEQ-like tracks

With WFS and VBAP, were large number of tracks are used it's not practical to apply the same effect to many tracks by using sends like in stereo mixing, because in WFS for instance this would mean processing 192 channels of audio. In the original WFS software, for master EQ this was solved by placing the eq ugens before the panners and sending the eq controls to all synths at the same time.

It would be interesting to generalize these capabilities to any unit, to be able to do post processing of a bunch of tracks, but still using the same trick of placing the post-processing units before the panners, but then having just one gui for all the post-processing units. Perhaps the processing units could be assigned to different "send groups" which are defined by a symbol like the UGroups, and then for each "send group" there would be only one gui to control all of the units at the same time. Off course this shouldn't apply just to GUIs, any change to one of those units should propagate to the other units, so that you could assign UMaps, etc.

Start by locating the existing WFS and VBAP panner abstractions, then read how UGroups, UMaps, GUIs, and sends are represented. Define how a symbol-named send group would connect multiple processing units while keeping them before the panners. Done means grouped units share GUI and control changes, including UMaps, across all assigned tracks.