In-ear monitors (IEMs) are devices used by musicians and audio professionals to deliver personalized and high-quality sound directly into the ears. These monitors fit snugly into the ear canal and provide a way for musicians to monitor their own performance or receive a mix of instruments and vocals during live performances. In-ear monitors offer improved sound isolation and clarity compared to traditional stage monitors, helping musicians hear themselves and their bandmates more accurately in noisy environments. They come in various designs, including custom-molded versions for an individual's ear shape, and are widely used in live music settings, recording studios, and broadcasting, providing a precise and customizable audio experience for performers.