Florian, 

thank you for your detailed response. I currently use my Dark Energy mk2 as an additional vco, envelope generator and LFO for my Dark Energy mk1.  I do this using the CV/gate inputs and outputs on each machine.  On this basis I would want the midi note information received by the Dark Energy mk1 to be forwarded also to the dark Energy mk2. As per section 3.4 (Linking and Stacking Dark Energies) of the Mark1 User Manual, engaging Stack Mode would actually prevent this. 

All I need now is to understand whether the 'slave' Dark Energy has to be set to the same midi channel as the 'master' using the Learn function, but I can find that out through experimentation.

Kind Regards,

Blair