Mains hum

Mains hum, often referred to as "60 Hz hum" in the United States or "50 Hz hum" in many other countries, is an audible electrical noise that is typically associated with alternating current (AC) power supply systems. **Causes of Mains Hum:** 1. **Power Frequency:** The hum arises because of the frequency of the AC power supply. In the U.S.