Wireless Microphone Systems
Sep 1, 2006 12:00 PM, By Bennett Liles
Versatility and simplicity rule in the new market.
Tips for Wireless Microphone Use
Sabine SWM7000 Smart Spectrum
The world of wireless microphones used to be simple. Back in the day, wireless systems were easy to set up and guaranteed not to work very well. But today, it's a whole new ballgame. For the most part, the new wave of technically advanced features in this line of products has been accompanied by a trend in imaginatively simple implementation.
While diversity reception in its various forms, automatic muting, auto scanning, and frequency selection, are not brand-new, the ways in which they have lately been combined, refined, and mixed with new options and control software are worth a close look. Encryption and other security measures have also matured. It's a crowded field, and each manufacturer has its own flavor of these features. In this issue, we'll take a look at what the market presently offers.
The WMS 4000 system from AKG Acoustics consists of the SR 4000 receiver, the HT 4000 handheld and PT 4000 body-pack transmitters, the CU 4000/BP 4000 charger and battery pack, and the PS 4000 antenna system. The receiver uses Tone Code Squelch (TCSQ) for combating interference; AutoSetup for quick and automated frequency selection; EnvironmentScan; and RehearsalMode, which records important system setup parameters during sound checks. The transmitters feature an output of 50mW with an audio frequency response of 35Hz to 20kHz and a switchable transmission range of up to 1,200 frequencies. Both have a backlit display showing frequency, gain setting, battery life, and lock/mute status. The charging system is standalone with two charging slots, each of which can hold the HT 4000, PT 4000, or spare BP 4000 battery. The AKG WMS 4000 systems range in price from $1,358 to $2,095, depending on configuration.
Among the lighter entries in operational complexity and price, the UHF 6400 system from Anchor Audio offers only features needed for quick and easy use. Twin-receiver diversity and tone muting bring in the signal for this 1/2RU unit, and it shows up on group/channel display and RF/AF meters with peak indicators. Controls include frequency select, volume setting, and manual squelch. Both balanced and unbalanced audio output connectors are available on the rear panel, while the front side offers a 1/4in. headphone jack. The front panel also has a DC output jack for charging the transmitter batteries. The WH-6400 and WB-6400 transmitters operate at 10mW and run 20 hours on a charge. The body-pack model includes a very handy mic/line input level switch. MSRP for receiver and one transmitter is $520.
Audio-Technica offers the Artist Elite 5000 wireless system built around rackmounted, twin receivers operating on any of 200 frequencies in each of two UHF bands. IntelliScan selects the best available channels for all linked receivers. Ethernet ports allow management via included AEW control interface software. The unit uses Tone Lock squelch to block stray RF and communicate transmitter data to the receiver. The receiver also has an AC pass-through feature to allow daisy-chaining of the power cables, thus avoiding the usual jumble of AC power strips. A 1/4in. jack allows operation of an external mute switch, and each system component can store up to five preset configurations. The MSRP varies from $3,119 to $4,719, depending on the combination of receiver and microphones ordered.
beyerdynamic Opus 800 MF
For wireless ENG/EFP, Azden markets the 200UPR, a 2-channel, camera-mounted UHF receiver that can be paired with several Azden wireless microphone transmitters. The unit has a -58dB mic-level mini jack for 2-channel output. Each channel has its own on/off switch, LEDs for power/signal receive, and group/frequency selector. The dual high-gain antennas attach with sturdy BNC connectors.
There's no need to buy new mics for this receiver; it's compatible with all of Azden's existing 100-, 400-, or 500-series 63-channel mic transmitters. Dual-channel, 3.5mm mini-to-XLR and mini-to-mini cables are supplied. The 200UPR slides right onto the camera with a hot-shoe mount, and can run for about eight hours on two AA batteries. The price of the 200UPR alone is $450. When the receiver is coupled with any two mics/transmitters, the MSRP begins at $850.
Behringer's UltraLink UL 2000M system uses twin-receiver diversity and auto-mute to deliver reception over three factory presets, each with eight permanent channels, and it offers storage for eight user-defined preset channels.
Up to 20 systems may be used simultaneously with the UL 2000M. With its cardioid polar pattern, the microphone affords high gain before feedback in multiple mic situations. The receiver's front panel features a power switch, volume control, channel display, dual-function set button, and up/down buttons to cycle through frequencies and presets. The set button is used to call up the menu and set selected menu values. LED ladders clearly display both RF and audio levels. Channel, frequency, and the receiver's mute status are constantly shown. The UL 2000M system currently lists for $250.
The computer-controlled Opus 800 system from beyerdynamic consists of one or more Opus 800 MF rack units with NE 800 plug-in receiver modules coupled with SDM 860, SDM 860 M, SDM 869, or SEM 881 handhelds, or the TS 800 or TS 800 M body-pack transmitters. The NE 800 features a color LCD showing frequency, group, channel, squelch status, battery level, user name, and RF/AF levels. Pilot tone muting and integrated limiter avoid interference and overloading.
The menu button can be held for five seconds to lock out all panel controls except the ACT button. The ACT function transmits the scan-selected receiver frequency by infrared link to the transmitter to automatically set it up for the channel. Compatible mic transmitters range in price from $269 to $599. The rack unit is $719, and the NE 800 receivers are $419. MSRP on the Opus 800 software is $599.
Electro-Voice REV-H handheld transmitter with four selectable heads
A quick, easy, and highly mobile solution for lighter wireless-mic needs can be found in the CW9000 system from Clockaudio. Operating in the UHF 630MHz-to-960MHz band with 192 PLL selectable channels, twin-receiver diversity reception and pilot tone muting, the CW9000R receiver displays active antenna, frequency, mute status, and RF/AF levels.
The front panel allows for frequency and volume settings, along with frequency scan to quickly locate clear channels. The rear panel offers balanced XLR and unbalanced 1/4in. connections. The CW9001T body-pack transmitter includes a power switch, AF level control, and frequency scan/select shown on the LC display. The CW9000T handheld mic incorporates similar features and has an interchangeable head with dynamic and condenser cardioid options. Each transmitter uses two AA batteries to run up to 10 hours.
Electro-Voice recently introduced the REV Series to the wireless world. Consisting of the REV-Single and REV-Dual receivers, the REV-BP body-pack transmitter, and the REV-H handheld transmitter with four selectable heads, the REV system can accommodate virtually any scenario in wireless performance. More than 40 units can run in one location using four separate UHF frequency bands.
The receiver features a backlit, menu-driven dot matrix display, DSP PosiPhase diversity reception, Tone Code plus adjustable amplitude squelch, XLR balanced mic/line level output, 12VDC powered antenna inputs, and CAN bus in/out ports that can run on the EV Iris-Net audio system. The handheld, interchangeable-head mics are machined aluminum with backlit displays. The retail price starts around $1,900 per channel.
For quick and easy setup and simple operation in a standalone environment, Gemini Sound markets the UZ series. The series is based on the UZ-1128 receiver, and is available with ZM-128 handheld mic or ZB-128 body-pack transmitter with mic/line input level switch — a useful addition not commonly found on body packs. As a UHF receiver, the ZB-128 can match with either the HSM-X4 headset or LAV-X4 lavalier microphones. The unit receives via single channel, switching diversity and pilot tone squelch. The blue, backlit LCD screen shows channel, frequency, and volume level. This complements the front-panel LED RF and AF level meters, power button, volume control, and channel select buttons. Outputs include a level adjustable headphone monitor, balanced XLR, and unbalanced 1/4in. connections. Depending on the components selected, the UZ Series retails from $319.95 to $349.95.
For professionals operating multiple microphones in a challenging environment, the Venue Receiver from Lectrosonics has pushed the envelope on sophistication and versatility. For maximum audio quality, the Digital Hybrid Wireless unit, with internal antenna multi-coupler, outputs digitally encoded audio received over FM analog transmission, but it can also operate in DSP emulation mode for compatibility with analog wireless systems.
The Venue Receiver Master (VRM) accepts plug-in receiver modules, which can be combined in pairs for ratio or frequency diversity reception or used individually for phase switched diversity. The plug-in receivers may be either the VRS with standard fixed-bandwidth front end or VRT with advanced frequency-tracking front end filters. Pilot tone-muting frequency is different for each channel in the tuning range. A 6-channel Venue receiver with six VRS receiver modules, six LM body-pack transmitters, and six M152 lavalier microphones carries an MSRP of $8,832.90, or $1,472.15 per channel. This price includes the internal multicoupler, an optional extra with most other brands.
One of the more interesting wireless mic systems is the LightSpeed Technologies 900iX 4-channel infrared wireless system, which is offered as an extension of the company's classroom amplification technology. Unlike earlier IR schemes, the system does not require line-of-sight transmission. It uses reflective distribution with sensitivity high enough to allow pickup by a single sensor in rooms up to 1,600 square feet. Additional sensors provide the capability to cover much larger spaces.
Samson Stage 55
The mic transmitter is capable of using Sennheiser, Audio-Technica, or Countryman mics, or the company's own LT-90 LightMic to beam the signal to a normally ceiling-mounted IR sensor. RG-59 cable takes the signal to the receiver, and it is output to an amplifier or mixer through XLR connections. Recommended for courtroom, corporate meeting room, and defense contractors, the 900iX lists security and interference rejection as primary advantages. With four transmitters, the unit's MSRP is $1,925.
Marking the company's 10th anniversary in March, Mipro introduced the ACT-81 single-channel and ACT-82 dual-channel receivers featuring 24-bit digital audio and digital modulation RF transmission along with 128-bit encryption via multi-phase combiner diversity. Mipro's ACT (Automatic Channel Targeting) system uses an AutoScan process to find a clear channel on the receiver. The ACT button is then pressed while the Mipro ACT-8H or ACT-8T microphone is held near the receiver's IR transmission port; the channel selection is automatically transmitted and set on the mic. Each of these microphones can run for up to eight hours on rechargeable lithium-polymer batteries. The front panel indicates all setup functions, and these are selected and controlled by a single rotary switch. The ACT 81 receiver MSRP is $3,000.
The U-1000 and U-2000 receivers from Nady Systems can be paired with the matching handheld, instrument body-pack, or lavalier body-pack microphones and operated with antenna-switching diversity over any of 1,000 UHF frequencies using Tone Squelch muting.
The unit features an RF scanning for automatic interference-free channel selection, and the channel information is conveyed by a USB connection to the matched transmitter. Outputs include balanced, mic-level XLR and 1/4in. connectors on the back panel. The UH-1000 handheld transmitter allows capsule selection with a snap-in condenser or dynamic QuickChange element. The mic also features a mute control, on/off switch, mute LED and LCD display. The versatile UB-1000 body-pack transmitter offers multiple, selectable inputs and gain settings compatible with the lavalier, headset, or instrument microphones. Depending on the configuration, the U-1000 Series system can retail for anywhere from around $750 to $1,350.
For traveling light and setting up quickly, the Peavey PCX U-302 receiver delivers 30 pre-programmed, user-selectable UHF channels, with groups one through four providing six channels each, and groups five and six each offering three channels. The rear panel has balanced XLR and 1/4in. connectors with a common mic/line level switch.
An AC adapter provides DC power, and a rear-mounted cable grip guards against accidental disconnection. Pilot-Tone and NoiseLock dual squelch combat interference, while the front panel provides group and channel selection/indication, RF and AF level LED meters, lighted power switch, antenna connectors, and volume control. RM-11 rack brackets allow the receiver to be rackmounted as a single unit. For dual units in a 1RU space, the RM-12 brackets are used. The MSRP is $680.
Revolabs has a unique product aimed primarily at the corporate conferencing and distance learning market. About the size of a flash drive, the Solo Executive wireless microphone clips on a shirt or jacket and transmits a 128-bit encrypted signal in the 1.9GHz band to an 8-channel receiver. The receiver can be linked with two additional receivers to handle up to 24 simultaneously operational microphones.
Receiver connections include synch in/out on Phoenix quick-connect terminal blocks, RJ-45, USB, and line-level audio in/out on Phoenix. The microphones are recharged after 1.5 hours in a single or group base unit and deliver a “talk time” of up to nine hours. Audio frequency response is 200Hz to 8kHz. The Revolabs Solo Executive system MSRP is $8,000.
The versatile Sabine SWM7000 Smart Spectrum series wireless system boasts a new range of features, including 2.4GHz band operation; parametric filters; compressor/limiter; active De-Esser; FBX Feedback Exterminator; and Microphone SuperModeling, which uses digital processing to emulate the sound character of seven different popular microphones. New SuperModel emulations may be downloaded from the company as they become available. All these integrated features save tons of clutter and outboard interconnects. The figure of 70 available channels means just that — all 70 can be used simultaneously. Control options include storage of 10 complete setups and selected access to all or just some of the front panel controls, along with remote control and parameter monitoring with the SWM7000 remote software. The receiver's ND variant includes digital audio output. The wide choice of system configurations with matched microphones lists from around $1,000 to just more than $2,000.
Perfect for budget-minded presenters and performers working in relatively benign RF environments, the Samson Stage 55 is the ultimate in simplicity. Using antenna-switched diversity reception, the receiver operates on a channel that is factory-set to use with a matched mic transmitter. The front panel includes LED ladder AF and RF level meters, a volume control, active antenna indicator, manual screwdriver-adjustable squelch setting, and power button. The rear panel presents a balanced XLR output that is mic/line switchable and a 1/4in. audio output. The AC adapter included supplies 12V DC for power. The Stage 55 may be used with either a frequency-matched ST5 body-pack mic transmitter or an HT5 handheld mic with integrated transmitter. Either one-mic/receiver configuration retails for $160 or less.
Techs setting up the Sennheiser G2 300 Series wireless mic systems can choose between eight switchable presets among 1,440 available frequencies over five UHF bands, and then keep track of multiple receivers by assigning an alpha-numeric name to each one. The LC display also shows peak hold and battery meter status. Audio output level is variable through XLR and 1/4in. connectors. The receivers can be matched with a variety of handheld mic models. With the SK 300 body-pack transmitter, several headset mics and instrument connections are available.
A thoughtful feature is the defeatable pilot tone squelch that makes the unit compatible with original EW systems. The 30mW transmitters can handle up to 154dB sound pressure levels. Depending on configuration, the G2 300 series systems are available in the $1,200 to $1,600 price range.
A recent addition to the Shure wireless product line, the UHF-R system can handle large shows with its ability to have a multitude of mics in simultaneous operation using multiple RF bands among its 2,400 selectable frequencies. Among the system's professional features are group scanning with automatic frequency selection, infrared link from receiver to transmitter for selected frequency communication, and menu-driven operation. Shure capitalizes on its traditional power in microphones by incorporating interchangeable mic capsules from its line of popular products. The UR2 handheld transmitter allows both frequency and power lockout on its LCD display. The single- and dual-receiver models each feature a flash memory for storage of six 60-channel frequency groups, a valuable time-saving feature for large shows. From single-channel receiver with one microphone to dual-channel with two mics, the price of the system ranges from around $1,500 to just less than $6,000.
Along with the advances in reception and interference rejection have come new innovations in system management. Sony's MB-X6 tuner base is a 1RU mainframe for mounting up to six WRU-806B or URX-M1 tuners. Space diversity reception includes dual BNC antenna mounts with 0/-10dB RF attenuation switches. Each balanced XLR audio output is mic/line switchable. The WRU-806B plug-in receiver features LED and LCD RF input status, audio output status, and battery alarm indications, while the URX-M1 shows the channel number and frequency on an LCD screen. The receivers can automatically search the channels of any pre-programmed group. The unit can be used with the WD-850A antenna divider, which lists for $1850. The WRU-806B lists for $550, the URX-M1 sells for $495, and the MSRP for the MB-X6 tuner rack is $800.
For the mid-range show size, Telex offers the FMR-500 system for simultaneous operation of 10 microphones among the preset groups in each band with digital Posi-Phase Diversity. The bands are 648MHz to 676MHz and 696MHz to 724MHz. One-button Auto ClearScan quickly finds clear channels for immediate use. The HT-500 handheld mic/transmitter incorporates a screw-on battery cover that also protects the channel selection buttons. A choice of mic heads is available between the Electro-Voice 767a and RE410. The WT-500 body-pack transmitter accommodates a wide variety of headset and lapel microphones with its TA4F connector. The receiver's backlit display shows group/channel, frequency, transmitter battery status, diversity operation, along with RF and AF level meters. The rear panel has balanced, mic/line switchable XLR and line-level 1/4in. outputs. The FMR-500 receiver, WT-500 body-pack transmitter, and HT-500 handheld microphone combination can be found for less than $700.
Just released this summer by TOA Electronics, the 5000 series can simultaneously operate up to 16 systems in the 692MHz-722MHz band. Receivers include the 64-channel WT-5800 with true diversity, the 64-channel space diversity WT-5805, and the WT-5810 portable space diversity with 16 channels. System transmitters include a handheld, body-pack, and two headset models, each of which can operate for up to 10 hours on a single AA battery.
The receiver's two-line front-panel display features scan mode revealing clear channels and transmitter battery status. The WT-5810 receiver uses a single LED readout to display the channel in use and incorporates a manual squelch control knob. The AEW5255D configuration with dual receiver and two handheld mics is available for less than $3,000.
The Zaxcom TRX900 has debuted with an amazing array of features that breaks new ground in the wireless mic world. The unit features digital transmission to its 1RU 4-channel RX4900 receiver, and can incorporate an integral IFB receiver and RF remote control with the IFB900. Options include 12-hour internal audio recording with timecode on a mini SD card, and the TRX 900 is available with AES encryption. The tiny body pack will run for five hours on a single 3V CR123 battery. The optional integrated IFB receiver operates in the 944-954Mhz band and provides 20Hz to 12kHz audio frequency response. The transmitter outputs 50mW, and up to 30 units in the same frequency block can be operated simultaneously. The TRX 900 has an MSRP of $1,650. The internal recording feature will add about $250.
Tips for Wireless Microphone Use
- Use active, external antennas when possible — particularly when operating multiple receivers. Best to use an antenna divider, but some receivers offer a loop-through.
- Directional antennas can be used in challenging RF environments.
- Keep body-pack antennas straight and unshielded by metallic objects.
- Even though more common 75V coax (RG-59) will work for short distances, use 50V (RG-58) coax for external antennas, and keep length to a minimum.
- Check local use of TV channels in advance and avoid those bands.
- Do not place antennas on catwalks or in other areas surrounded by metal.
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Bennett Lilesis a freelance television production engineer and audiovisual technician in the Atlanta area. He specializes in government video production, distance learning, and videoconferencing.