Why In-Ear Monitors Drop Out

Understanding Polarization

It is essential for in-ear monitor systems to get a good signal to the bodypack receiver. Many belt pack receivers only have a single antenna, which is a big barrier to getting great reception. Receivers like this are more likely to drop out than the dual antenna diversity systems that are common in wireless microphones and higher-end IEMs. Another thing that can make an IEM encounter dropouts is that the belt pack is in motion, so the position of the person wearing it can interfere with the signal. Plus, the pack sits beside or behind the person using it, requiring the signal to pass through or alongside their body, which is nontransparent for RF energy.

Use a Helical Antenna 

Helical antennas are the top antenna choice for IEM transmission because the circular motion of the RF field distributes the signal through all possible polarization angles. This removes the greatest risk of dropouts since most IEM belt packs have only a single whip antenna.

Use An IEM Combiner

When you are using an in-ear monitor system, using a combiner is especially important. Without it, multiple IEM transmitters will end up transmitting on top of each other, which can be a disaster for your system. These antenna farms create noise and intermod problems that can wreak havoc on both IEM performance and neighboring wireless microphones. The solution is a clean rack with an IEM combiner and a helical antenna.

"At the end of the day it is all about hearing what is spoken. RF Venue systems give you the tools and the confidence to produce reliable and repeatable results that make sure the word is heard!"  - Vox Church

 

Coordinate IEM frequencies with wireless mics

The more wireless devices that are in a space, the more difficult it becomes to maintain reliable performance. More devices require more empty space to operate in, and since the spectrum is constantly shrinking, empty space is hard to come by. In addition, every time you turn on another transmitter, you increase the amount of intermod in your workspace.

Use bandpass filters for wireless mics when running IEMs

Bandpass filters allow the frequencies inside the bandpass range to pass through unaffected but block RF from outside the bandpass — the signals from the IEMs — from getting into the receivers for the wireless mics. This means that, as far as the wireless mic receivers are concerned, the in-ear monitor  signals will be knocked down by about 40db, so they will not interfere with your wireless microphones.