# Cable Colors Patch cables in these notes are color-coded by function, after [Chris Meyer at Learning Modular](https://learningmodular.com/choosing-patch-cables/). Chris codes by what a cable carries, not by length. He arrived at the colors from the banana-jack coding on Buchla and Serge systems, plus the colors cable makers commonly stock. ## The six colors | Color | Carries | Typical jacks | How to tell | | --- | --- | --- | --- | | ⚪ Gray (silver) | 1 V/octave pitch | V/OCT, 1V/OCT, KB, a quantized pitch output | It sets the note | | 🔵 Blue | modulation voltages | CUTOFF, MORPH, TIME, FOLD, BLEND, LEVEL, MIX, Z, an envelope or LFO output into a non-pitch input | It moves a parameter | | 🟡 Yellow | audio signals | OUT, VCA, IN, IN L, IN R, EXT. AUDIO, ODD, EVEN | It's the sound, including cables into the A-540 or A-541 | | 🔴 Red | gates and triggers | GATE, TRIG, TRIGGER, STRUM, a gate or pattern output | It starts a note, a hit, or an event | | 🟢 Green | clock signals for sync | CLOCK, ADV/CLOCK, ASSIGN when it's the sequencer clock, a tap-tempo clock, a clock input | It keeps two things in time | | ⚫ Black | external connections | RCA from a turntable, a rear 1/4″ output to a mixer, a cable to speakers | It enters or leaves the rack | ## Judgment calls A few cables could wear two colors. These notes use the following rules: - A clock used to strike or strum something is red. - A clock that only drives a clock or sequencer input is green. - Random CV into V/OCT is gray. - CV into anything else is blue. - Internal audio into the A-540 or A-541 is yellow. - Anything going out to outside gear is black. Cables to the Mini Speakers are black; they feed speakers. Cables into the A-540 or A-541 stay yellow. If a line in a patch note is still a close call, it's marked "(judgment call)". Chris also puts colored cable ties on the ends of same-color cables so he can tell them apart at a glance, for example when several blue cables leave one module.