A quad driver in the context of earphones or headphones refers to a type of earphone or headphone that uses
four different balanced armature drivers to reproduce sound. Each driver is responsible for a specific frequency range (e.g., low, mid-bass, midrange, treble), allowing for a more detailed and accurate sound reproduction compared to earphones with fewer drivers.
The idea is that by dividing the frequency range among specialized drivers, each driver can be optimized for its specific task, resulting in improved clarity, detail, and overall sound quality. This is different from using a single dynamic driver which handles the entire frequency range.
