Acoustics is the science of sound. Sound travels in waves and these waves bounce off surfaces in the room in which the musician is playing. If these waves become stacked on top of each other, the music becomes cacophonous. Some surfaces, such as concrete and brick, are more bouncy than others, and if these surfaces are flat they make it easier for the waves to stack. Carpet and wood, however, absorb some of the wave and help to keep the waves from stacking on each other.
Hearing loss is a major concern for all musicians. In 1981, a study done in Sweden showed that 42 percent of orchestra musicians had hearing losses that were greater than were expected for their ages. That percentage goes up for other types of musicians because they are playing louder music for more extended periods of time. A good set of in-ear monitors can help to ease this process. They allow you to have a better sound at a lower volume. They also help to block out other noise that might cause hearing loss.
In-ear monitors are small headphones that can be placed in the ear canal. They block the ear canal so the only thing you are hearing is the noise that you're running through your in-ear monitor system. That gives you better clarity, which makes it easier to play more precisely. What gives you better clarity is the amount of drivers in the monitors. The drivers are basically small speakers inside the monitors. The more drivers you have, the clearer the sound coming through will be. Some monitors only have two drivers, while some go as high as six drivers.
In-ear monitors are not the only thing you need to use them. You also need a system that powers the monitors and delivers sound to the drivers. Most of these systems are wireless, allowing you to move freely about the stage. The systems usually come with a transmitter, two to four body packs that receive the sound from the transmitter and a corresponding number of headphones. However, it is possible to purchase your own set of headphones if the ones that come with the system don't produce the clarity you're looking for.