Coordination. TV broadcasts are the dominant feature of the local RF spectrum. Online resources like the Sennheiser Frequency Finder, which uses a ZIP code, and the FCC’s database to provide a list of local TV broadcast stations and their signal strength, helps users tune wireless systems to interference-free frequencies, removing much of the guesswork.
Antenna. Most wireless in-ear monitoring transmitters come with a simple quarter-wave whip antenna, which is fine for single systems at close distances. Multiple systems benefit from both an antenna combiner as well as a directional antenna that also provides RF gain.
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A Log-Periodic Dipole Array (LPDA ) antenna, called a “shark fin” or “paddle,” provides 6 dB of gain and is thin enough to slip into the back of a rack. A Helical antenna provides about 10 dB of gain plus the advantage of circular polarization.
Molds. Custom molded earphones provide a snug, comfortable fit with a tight seal that not only improves low frequency response, but also provides up to 26 dB of isolation, allowing performers to monitor at lower volumes, which aids hearing conservation and reduces hearing fatigue.
Inexpensive generic earphones can be uncomfortable, don’t provide enough seal in the ear to ensure good low frequency response, and their reduced isolation can contribute to higher monitoring levels.
Both Ears. Using just a single earphone leads to higher monitoring volumes, as performers raise its volume to match the ambient stage sound in the other ear, removing any hearing conservation benefits.
Stereo. Listening to stereo-panned mixes contributes to lower monitoring levels because it is easier to hear individual instruments that are panned across a stereo field than by listening to a mono mix. Lower monitoring levels contribute to hearing conservation.
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Dynamics. Since many performers employ a fairly full mix, dynamics management can help build mixes that can sail smoothly through the relatively narrow dynamic range of analog wireless systems.
Compression on a singer’s microphone in their own mix can contribute to vocal strain, but compression on instruments keeps them from clipping a wireless transmitter’s input.
Multi-band compression on each monitor mix can allow the mid-range to be better heard, while keeping low- and high-frequency transients from clipping the transmitter.