Proscenion is an open stage simulation tool for the Jack Audio Connection Kit. This program allow you to position your audio sources on the stage and capture the 'close-to-reality' stereo result, both in phase and level, assuming the capture behaves like a dual microphone dummy head. It's like a stereo mixer, but with real stereo.
Proscenion program is free software, copyright (C) 2018 Benoît Rouits and released under the GNU General Public Lisence version 3. It is delivered as is in the hope it can be useful, but with no warranty of correctness.
Proscenion source code is browsable at the GNOME's Gitlab as a side project (not par of GNOME). You can checkout it with a git client program, or download it as a zip archive.