Banana Jack Color Code for Modular Synthesizer System
(Oct ‘14)
INPUTS:
RED = dc coupled input. Can be audio or CV.
GREY = ac coupled input. (Usually means “audio only, please” as opposed to a trigger input.)
GREEN = Gate input. Expects a positive going voltage, usually +5 to +12. dc coupled, the input will stay at the gate voltage.
WHITE = Trigger input. Same a gate, except an input cap blocks steady signals so the input will only respond to the initial positive going voltage.
PURPLE = Sync input.
OUTPUTS:
BLUE = General, non-gate/trig output. Can be audio or CV.
ORANGE = Gate output. +10 usually, up to +12.
YELLOW = Trigger or clock output.
OTHER:
BLACK = 0V/Ground reference. This is connected directly to the panel. Usually for special connections to external equipment.
Most modules have been designed with the expectation that accidental connections can and will happen, so experimentation is largely OK. Stacking of banana jacks is OK.
Most inputs have a 100k dc impedance.
Most outputs have a 1k dc impedance. Some GATE outputs may be as low as 100Ω.