In theory, wireless microphone systems are a godsend to video producers. Deploy it on the talent, plug the receivers into the production board/camcorder, activate the transmitters and receivers, and go.
Wireless microphone systems when properly selected can indeed achieve that level of ease of use in practice. But choose wrong and you could end up with a bug-ridden system that makes production more difficult than a wired alternative would.
IMPORTANT POINTS TO CONSIDER
Wireless microphone systems are all about radiowave transmission, and the radio waves being used — either VHF or UHF — can affect how well a signal travels, as well as how resistant they are to interference from other sources.
UHF is often a better choice simply because there are so many more open channels available, thereby reducing the risk of interference. However, if the production is in an area with few VHF sources, this lower-cost option can be a good alternative.
In addition, wireless-microphone systems are available with analog or digital transmitters. The advantage of digital is that the audio signal is converted into data before transmission, then converted back to audio during reception. That eliminates the chance of crosstalk interference from other audio sources.
The advantage of analog is that its signals do not drop out the way digital does (the so-called “cliff effect”). Rather, analog signals fade, which means such a system might produce a usable audio signal in conditions where digital signals might be lost.
The term “diversity” is attached to higher-end wireless systems. That means the receiver uses two antennas rather than one, enabling the system to select the stronger signal source. Such a system has a better chance of achieving reliable signal reception, due to its access to a diversity of signals.
Further, wireless-microphone systems are available in head-worn, handheld and lapel configurations. Generally, head-worn systems are over-the-ear mics worn by speakers for presentations, while handhelds are best suited for field work, where rugged, noise-resistant audio pickup is a must and lapel mics (also known as a lavalier or a clip-on) work best in studios, where the guests are seated and not moving around.
Finally, there are cardioid/unidirectional and omnidirectional microphones. Cardioid mics are designed to pick up audio directly in front of the microphone and reject sound coming from other directions, which makes those mics well-suited for interviews in outdoor conditions, or where other sources of sound are close by.
Omnidirectional mics pick up sound equally well from all directions. That makes them useful when used on head-worn systems because the speaker is the only audio source within range; omnidirectionals are also used to collect wild sound on location.
Now that the basics have been covered, a listing of some wireless-microphone vendors and their products is appropriate.
Audio-Technica’s 1800 Series A wireless-microphone system that enables two mics to be operational simultaneously is the Audio- Technica 1800 Series UHF camera-mount wireless microphone. The 1800 Series is available in dual channel and single-channel systems, and its dual balanced outputs enable signals to be mixed, or independently assigned to each output. The 1800 Series offers a choice of a plug-on transmitter with four-pin connector or a body-pack transmitter with XLR connector for adapting dynamic and condenser microphones.
“With 996 frequencies available in two different frequency bands, the Audio-Technica 1800 Series wireless allows for greater flexibility in the crowded UHF spectrum,” said David Marsh, Audio-Technica’s director of sales and marketing, broadcast. “Both the single and dual receivers offer auto-scan for ease of finding useable frequencies, regardless of your location.”
Azden’s 310ULT There are two wireless- microphone systems available from Azden starting with the company’s 310ULT, a diversity, single channel UHF camera- mount wireless system providing access to 188 user selectable frequencies. Designed to be used by talent wearing a 35BT body pack and EX-503L lapel mic, the camera shoe-mounted 330UPR receiver has pivoting high-gain antennas, a digital liquid crystal display with multifunction readout, a mini jack output with mini and XLR cables included and a headphone output on the receiver.
Azden’s 330ULT system provides a diversity based dual-channel UHF camera-mount wireless system with the same features as the 310ULT. To support two channels, the system is equipped with two 35BT body packs and two EX-503L clip mics, plus the camera-mounted 330UPR receiver.
DPA Microphones’ d:facto II Vocal Microphone The latest wireless microphone from DPA Microphones is the d:facto II Vocal Microphone, which provides compatibility with the top wireless transmitters, a high sound pressure level handling up to 160 dB and no handling noise. The d:facto II uses a super-cardioid polar pattern, which means it rejects audio coming in from the sides of the unit, DPA said.
“DPA is internationally acclaimed for delivering the pristine sound quality that broadcasters and their viewers want, which we have once again done with the d:facto II,” said Christian Poulsen, DPA Microphones’ CEO. “We are extremely proud to have developed an ingenious adapter range that brings the true DPA sound out of a high-powered wireless system.”
Electro-Voice’s R300 Providing 32 preset channels is the Electro-Voice R300 wireless system. Among the features offered by the R300 are the ClearScan one-button clear channel finder and the EZsync infrared-channel transfer, which transfers from receiver to transmitter, enabling fast setups, according to the company.
The system is available in three configurations, the R300-E head worn system, which is equipped with a HM-3 omnidirectional microphone for lecturers and keynote speakers; the R300-HD, which has a PL22 cardioid dynamic handheld mic, and is well-suited for field production; and the R300-L lapel system, which has a clip-on ULM18 directional microphone for in-studio applications. Electro-Voice also makes the RMD-300 Dual Rack Mount Kit that enables two R300 receivers to be mounted inside a standard 19-inch rack unit.
Lectronics’ WM For those who need to work in wet or dusty environments, Lectrosonics’ WM watertight beltpack transmitter is suited to the task. It is equipped with O-ring sealed battery compartments and input jack, a compression sealed antenna port, and gasket sealed control panel and back cover, according to Lectrosonics. Large membrane switches and control pane, plus a backlit LCD display make the WM reliable and easy to use, the company said.
Other WM features include output-power selection that can maximize battery life or operating range, a corrosion-resistant aluminum housing, programmable compatibility modes for use with a variety of receivers, and Servo Bias input circuitry with selectable voltage, the company said.
Sennheiser’s SKM 2000 A number of wireless microphone solutions for video producers are offered by Sennheiser, including the SKM 2000. In terms of handheld transmitters, the SKM 2000 features a 75 MHz bandwidth with frequencies tunable in 25 kHz steps. While the SKM 2000 will operate for eight hours on two AA batteries, the unit can cater to different transmission environments by switching power output from 10 mW, to 30 mW to 50 mW and up to 100 mW within the United States.
Sennheiser’s Evolution wireless series offers the SKM 100 G3 handheld and SK 100 G3 body-pack transmitters, which feature a 42 MHz switching bandwidth. The transmission frequencies are tunable in 25 kHz steps and their output power is 30 mW; they will also operate for eight hours on two AA batteries.
On the camcorder side, Sennheiser’s EK 100 G3 receiver pack can sit on any camcorder shoe and wirelessly connect to either a handheld microphone or a belt-pack with a clip-on lavalier. The unit has a 42 MHz bandwidth, enabling communication with 1,680 tunable UHF frequencies for interference-free reception. In addition, the EK 2000 camera receiver goes further by providing access to 3,000 available frequencies over a 75 MHz bandwidth.
Shure’s BLX2 wireless microphone and its BLX4R rack-mountable receiver Available in both handheld and lapel-style configurations is Shure’s new BLX Wireless System, which is designed to deliver professional-grade sound with a fast easy setup, the company said. The microphones have up to 300 feet of effective range; to help avoid interference, Shure’s one-touch QuickScan locates the best open frequency available.
The BLX Wireless System will operate for up to 14 hours on a pair of AA batteries. The system’s components include the BLX1 body-pack transmitter, the BLX2 handheld transmitter, the BLX4 single-channel receiver, the BLX4R rack-mountable receiver and the BLX88 dual-channel receiver.
Other Shure wireless-microphone systems include the PGX14/185 lapel-microphone system, PGX14/PG30 head-worn microphone system and the PGX24/SM58 handheld-microphone system that uses the SM58 handheld mic.