The ART CableCOP features a full selection of standard pro audio connectors for testing all such cables. LEDs on the ART CableCOP link its various connector terminals and will only illuminate when the connected ‘cable’ completes a circuit. As a result you’re able to tell, at a glance, which cables need to be repaired. Sometimes the problem can be the cable itself. An LED may also fail to illuminate if a 3-conductor cable has been wired out-of-phase. As an example, if the Tip of one 1/4” TRS plug on a (balanced) patch cable were soldered to the same cable conductor as the Ring or Sleeve of the other 1/4” inch TRS plug.