What is the BEST PRACTICE for deciding between unbalanced and balanced audio cables?

The best practice for deciding between unbalanced and balanced audio cables is to utilize balanced cables for all runs exceeding 50 feet (15.2 meters). This approach is based on the performance characteristics of the two types of cables. Balanced cables are designed to reject electromagnetic interference (EMI) and radio frequency interference (RFI) through a technique of phase cancellation. As cable lengths increase, the potential for interference also increases, making balanced cables a superior choice for longer runs.

In environments with high electromagnetic interference, which can be common in live sound or installations near other electronic devices, using balanced cables helps maintain audio quality by minimizing noise and ensuring a clean signal. Therefore, the recommendation to use balanced cables for runs over 50 feet is grounded in practical experience and technical standards in the AV industry, prioritizing sound fidelity and reliability over longer distances. This practice helps to maximize the effectiveness of the audio system and is generally considered industry standard.