In-ear monitor

They are often custom-fitted to an individual's ears to provide comfort and a high level of noise reduction from ambient surroundings.

First, floor wedges greatly increase the onstage volume, in some cases to levels which could potentially damage hearing.

Larger live shows can have several microphones for this purpose spread across the front of the stage, which can also be sent to a multitrack recording device used in an outside broadcast production truck, or other destinations.

[citation needed] Most professional stage in-ear monitor systems use wireless technology to send the mix to the IEMs.

This type of system consists of a stationary offstage transmitter and an onstage receiver (about the size of a deck of cards) that is worn by the performer.

Universal IEMs typically include a variety of foam and silicone tips in each pack, with the goal that one pair may create a comfortable seal for the user's ears.

If a universal IEM earpiece does not fit a specific person, they may need to order custom in-ear monitors.

The IEM cable plugs into a 3.5 mm stereo jack on the receiver pack; typically clipped onto the belt, guitar strap, clothing of the performer, or placed in a pocket.

Custom in-ear monitors made of a softer silicone material can be inserted deeper in the ear canal and will provide more isolation from outside noise.

[5][4] Television studios use earpieces with a specialized type of intercom called an interruptible foldback (IFB), as a means of communication.

Originally invented for hearing aids, balanced armature drivers are nowadays used extensively in modern in-ear monitors.

When an electric current passes through, the voice coil vibrates between the two permanent magnets resulting in the diaphragm moving and producing sound.

Similar to dynamic drivers, electric current is passed through the magnets causing the diaphragm to produce sound.

Wire down is easier to put in with one hand, making it more popular for casual use, where it maybe inserted and removed multiple times per day.

Some wires may come with MMCX connectors to allow replacement once worn out, add-ons like in-line microphone or bluetooth connectivity or upgrading to cables of higher quality or different appearance.

Removing one IEM negates the improvement in signal-to-noise ratio from isolation and the binaural summation effect which causes an increase in perceived loudness from using two sound sources.