If we want musicians to be able to use the i8 as a standalone synthesizer (with or without external controller), we need a way to mix its 8 polyphonic channels. For that, we should embed a mixer.
In order to keep things simple and keep the number of analog crosspoint switches to a minimum, we could make some assumptions on the nature of the 6 analog ports offered by each channel. When you look at many Eurorack modules, you will find that a large fraction of them include either one monophonic output, or two stereophonic ones.
Therefore, we could assume that many of our submodules will have such outputs. And when they do, we should assume that ports A4 and A5 are used for it, with the following mapping:
- Monophonic output: A5
- Stereophonic output: Left on A4, Right on A5
With such assumptions, we could statically route our 16 A4 and A5 channels to a couple of mixers, one monophonic and one stereophonic. From there, a double click on any of the A5 knobs (bottom knobs) would switch the module to mixing mode, allowing all A4 and A5 knobs to be used for mixing purposes. And we would use the USB port for audio out.
Now, we need to find the right component for mixing analog signals.