How did compact fluorescent lamps reduce the buzzing associated with older fluorescent fixtures?

Compact fluorescent lamps (CFLs) reduce the audible humming or buzzing noise common in older fluorescent fixtures by utilizing electronic components within their integrated ballasts.1

In traditional fluorescent lighting, the ballast—a device required to regulate the voltage needed to ionize the gas—is typically a separate, bulky component that often produces an audible hum. In contrast, compact fluorescent lamps feature a miniaturized ballast nested directly into the base of the bulb assembly. By using modern electronic components rather than the older magnetic designs, these integrated ballasts effectively eliminate the buzzing sound associated with legacy fixtures.1