Chromaphone 3’s Couple feature adds more nuance by processing the two Resonators in parallel or sequence. When coupling is off, the two resonators are activated independently, and the Balance slider controls the volume mix of the two sources. This is closer to how physical modelling synths have worked in the past.
However, when the two Resonators are coupled, they work more like a real instrument – the energy used to activate A feeds into B. Some of B’s energy is then reflected back into A and you get a complex, interactive feedback loop between Resonators. In the coupled configuration, the Balance slide controls how much energy transfer occurs between the two resonators.
Coupled or uncoupled? Chromaphone can do both